text:
Network Working Group | R. Fielding, Editor |
Internet-Draft | Day Software |
Obsoletes: 2616 (if approved) | J. Gettys |
Intended status: Standards Track | One Laptop per Child |
Expires: July 15, 2008 | J. Mogul |
H. Frystyk | |
Microsoft | |
L. Masinter | |
Adobe Systems | |
P. Leach | |
Microsoft | |
T. Berners-Lee | |
Y. Lafon, Editor | |
J. Reschke, Editor | |
greenbytes | |
January 12, 2008 |
By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is aware have been or will be disclosed, and any of which he or she becomes aware will be disclosed, in accordance with Section 6 of BCP 79.¶
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The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt.¶
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This Internet-Draft will expire on July 15, 2008.¶
The Hypertext Transfer Protocol (HTTP) is an application-level protocol for distributed, collaborative, hypermedia information systems. HTTP has been in use by the World Wide Web global information initiative since 1990. This document is Part 2 of the seven-part specification that defines the protocol referred to as "HTTP/1.1" and, taken together, obsoletes RFC 2616. Part 2 defines the semantics of HTTP messages as expressed by request methods, request-header fields, response status codes, and response-header fields.¶
Discussion of this draft should take place on the HTTPBIS working group mailing list (firstname.lastname@example.com). The current issues list is at <http://www.tools.ietf.org/wg/httpbis/trac/report/11> and related documents (including fancy diffs) can be found at <http://www.tools.ietf.org/wg/httpbis/>.¶
This draft incorporates those issue resolutions that were either collected in the original RFC2616 errata list (<http://purl.org/NET/http-errata>), or which were agreed upon on the mailing list between October 2006 and November 2007 (as published in "draft-lafon-rfc2616bis-03").¶
This document defines HTTP/1.1 request and response semantics. Each HTTP message, as defined in [Part1], is in the form of either a request or a response. An HTTP server listens on a connection for HTTP requests and responds to each request, in the order received on that connection, with one or more HTTP response messages. This document defines the commonly agreed upon semantics of the HTTP uniform interface, the intentions defined by each request method, and the various response messages that might be expected as a result of applying that method for the requested resource.¶
This document is currently disorganized in order to minimize the changes between drafts and enable reviewers to see the smaller errata changes. The next draft will reorganize the sections to better reflect the content. In particular, the sections will be ordered according to the typical processing of an HTTP request message (after message parsing): resource mapping, general header fields, methods, request modifiers, response status, and resource metadata. The current mess reflects how widely dispersed these topics and associated requirements had become in [RFC2616].¶
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119].¶
An implementation is not compliant if it fails to satisfy one or more of the MUST or REQUIRED level requirements for the protocols it implements. An implementation that satisfies all the MUST or REQUIRED level and all the SHOULD level requirements for its protocols is said to be "unconditionally compliant"; one that satisfies all the MUST level requirements but not all the SHOULD level requirements for its protocols is said to be "conditionally compliant."¶
Product tokens are used to allow communicating applications to identify themselves by software name and version. Most fields using product tokens also allow sub-products which form a significant part of the application to be listed, separated by white space. By convention, the products are listed in order of their significance for identifying the application.¶
product = token ["/" product-version] product-version = token
User-Agent: CERN-LineMode/2.15 libwww/2.17b3 Server: Apache/0.8.4
Product tokens SHOULD be short and to the point. They MUST NOT be used for advertising or other non-essential information. Although any token character MAY appear in a product-version, this token SHOULD only be used for a version identifier (i.e., successive versions of the same product SHOULD only differ in the product-version portion of the product value).¶
The Method token indicates the method to be performed on the resource identified by the Request-URI. The method is case-sensitive.¶
Method = "OPTIONS" ; Section 8.2 | "GET" ; Section 8.3 | "HEAD" ; Section 8.4 | "POST" ; Section 8.5 | "PUT" ; Section 8.6 | "DELETE" ; Section 8.7 | "TRACE" ; Section 8.8 | "CONNECT" ; Section 8.9 | extension-method extension-method = token
The list of methods allowed by a resource can be specified in an Allow header field (Section 10.1). The return code of the response always notifies the client whether a method is currently allowed on a resource, since the set of allowed methods can change dynamically. An origin server SHOULD return the status code 405 (Method Not Allowed) if the method is known by the origin server but not allowed for the requested resource, and 501 (Not Implemented) if the method is unrecognized or not implemented by the origin server. The methods GET and HEAD MUST be supported by all general-purpose servers. All other methods are OPTIONAL; however, if the above methods are implemented, they MUST be implemented with the same semantics as those specified in Section 8.¶
The request-header fields allow the client to pass additional information about the request, and about the client itself, to the server. These fields act as request modifiers, with semantics equivalent to the parameters on a programming language method invocation.¶
request-header = Accept ; [Part3], Section 5.1 | Accept-Charset ; [Part3], Section 5.2 | Accept-Encoding ; [Part3], Section 5.3 | Accept-Language ; [Part3], Section 5.4 | Authorization ; [Part7], Section 3.1 | Expect ; Section 10.2 | From ; Section 10.3 | Host ; [Part1], Section 8.4 | If-Match ; [Part4], Section 6.2 | If-Modified-Since ; [Part4], Section 6.3 | If-None-Match ; [Part4], Section 6.4 | If-Range ; [Part5], Section 5.3 | If-Unmodified-Since ; [Part4], Section 6.5 | Max-Forwards ; Section 10.5 | Proxy-Authorization ; [Part7], Section 3.3 | Range ; [Part5], Section 5.4 | Referer ; Section 10.6 | TE ; [Part1], Section 8.8 | User-Agent ; Section 10.9
Request-header field names can be extended reliably only in combination with a change in the protocol version. However, new or experimental header fields MAY be given the semantics of request-header fields if all parties in the communication recognize them to be request-header fields. Unrecognized header fields are treated as entity-header fields.¶
The Status-Code element is a 3-digit integer result code of the attempt to understand and satisfy the request. The status codes listed below are defined in Section 9. The Reason-Phrase is intended to give a short textual description of the Status-Code. The Status-Code is intended for use by automata and the Reason-Phrase is intended for the human user. The client is not required to examine or display the Reason-Phrase.¶
The individual values of the numeric status codes defined for HTTP/1.1, and an example set of corresponding Reason-Phrase's, are presented below. The reason phrases listed here are only recommendations -- they MAY be replaced by local equivalents without affecting the protocol.¶
Status-Code = "100" ; Section 9.1.1: Continue | "101" ; Section 9.1.2: Switching Protocols | "200" ; Section 9.2.1: OK | "201" ; Section 9.2.2: Created | "202" ; Section 9.2.3: Accepted | "203" ; Section 9.2.4: Non-Authoritative Information | "204" ; Section 9.2.5: No Content | "205" ; Section 9.2.6: Reset Content | "206" ; Section 9.2.7: Partial Content | "300" ; Section 9.3.1: Multiple Choices | "301" ; Section 9.3.2: Moved Permanently | "302" ; Section 9.3.3: Found | "303" ; Section 9.3.4: See Other | "304" ; Section 9.3.5: Not Modified | "305" ; Section 9.3.6: Use Proxy | "307" ; Section 9.3.8: Temporary Redirect | "400" ; Section 9.4.1: Bad Request | "401" ; Section 9.4.2: Unauthorized | "402" ; Section 9.4.3: Payment Required | "403" ; Section 9.4.4: Forbidden | "404" ; Section 9.4.5: Not Found | "405" ; Section 9.4.6: Method Not Allowed | "406" ; Section 9.4.7: Not Acceptable | "407" ; Section 9.4.8: Proxy Authentication Required | "408" ; Section 9.4.9: Request Time-out | "409" ; Section 9.4.10: Conflict | "410" ; Section 9.4.11: Gone | "411" ; Section 9.4.12: Length Required | "412" ; Section 9.4.13: Precondition Failed | "413" ; Section 9.4.14: Request Entity Too Large | "414" ; Section 9.4.15: Request-URI Too Large | "415" ; Section 9.4.16: Unsupported Media Type | "416" ; Section 9.4.17: Requested range not satisfiable | "417" ; Section 9.4.18: Expectation Failed | "500" ; Section 9.5.1: Internal Server Error | "501" ; Section 9.5.2: Not Implemented | "502" ; Section 9.5.3: Bad Gateway | "503" ; Section 9.5.4: Service Unavailable | "504" ; Section 9.5.5: Gateway Time-out | "505" ; Section 9.5.6: HTTP Version not supported | extension-code extension-code = 3DIGIT Reason-Phrase = *<TEXT, excluding CR, LF>
HTTP status codes are extensible. HTTP applications are not required to understand the meaning of all registered status codes, though such understanding is obviously desirable. However, applications MUST understand the class of any status code, as indicated by the first digit, and treat any unrecognized response as being equivalent to the x00 status code of that class, with the exception that an unrecognized response MUST NOT be cached. For example, if an unrecognized status code of 431 is received by the client, it can safely assume that there was something wrong with its request and treat the response as if it had received a 400 status code. In such cases, user agents SHOULD present to the user the entity returned with the response, since that entity is likely to include human-readable information which will explain the unusual status.¶
The response-header fields allow the server to pass additional information about the response which cannot be placed in the Status-Line. These header fields give information about the server and about further access to the resource identified by the Request-URI.¶
response-header = Accept-Ranges ; [Part5], Section 5.1 | Age ; [Part6], Section 15.1 | ETag ; [Part4], Section 6.1 | Location ; Section 10.4 | Proxy-Authenticate ; [Part7], Section 3.2 | Retry-After ; Section 10.7 | Server ; Section 10.8 | Vary ; [Part6], Section 15.5 | WWW-Authenticate ; [Part7], Section 3.4
Response-header field names can be extended reliably only in combination with a change in the protocol version. However, new or experimental header fields MAY be given the semantics of response-header fields if all parties in the communication recognize them to be response-header fields. Unrecognized header fields are treated as entity-header fields.¶
Request and Response messages MAY transfer an entity if not otherwise restricted by the request method or response status code. An entity consists of entity-header fields and an entity-body, although some responses will only include the entity-headers. HTTP entity-body and entity-header fields are defined in [Part3].¶
An entity-body is only present in a message when a message-body is present, as described in Section 4.3 of [Part1]. The entity-body is obtained from the message-body by decoding any Transfer-Encoding that might have been applied to ensure safe and proper transfer of the message.¶
The set of common methods for HTTP/1.1 is defined below. Although this set can be expanded, additional methods cannot be assumed to share the same semantics for separately extended clients and servers. The Host request-header field (Section 8.4 of [Part1]) MUST accompany all HTTP/1.1 requests.¶
Implementors should be aware that the software represents the user in their interactions over the Internet, and should be careful to allow the user to be aware of any actions they might take which may have an unexpected significance to themselves or others.¶
In particular, the convention has been established that the GET and HEAD methods SHOULD NOT have the significance of taking an action other than retrieval. These methods ought to be considered "safe". This allows user agents to represent other methods, such as POST, PUT and DELETE, in a special way, so that the user is made aware of the fact that a possibly unsafe action is being requested.¶
Naturally, it is not possible to ensure that the server does not generate side-effects as a result of performing a GET request; in fact, some dynamic resources consider that a feature. The important distinction here is that the user did not request the side-effects, so therefore cannot be held accountable for them.¶
Methods can also have the property of "idempotence" in that (aside from error or expiration issues) the side-effects of N > 0 identical requests is the same as for a single request. The methods GET, HEAD, PUT and DELETE share this property. Also, the methods OPTIONS and TRACE SHOULD NOT have side effects, and so are inherently idempotent.¶
However, it is possible that a sequence of several requests is non-idempotent, even if all of the methods executed in that sequence are idempotent. (A sequence is idempotent if a single execution of the entire sequence always yields a result that is not changed by a reexecution of all, or part, of that sequence.) For example, a sequence is non-idempotent if its result depends on a value that is later modified in the same sequence.¶
A sequence that never has side effects is idempotent, by definition (provided that no concurrent operations are being executed on the same set of resources).¶
The OPTIONS method represents a request for information about the communication options available on the request/response chain identified by the Request-URI. This method allows the client to determine the options and/or requirements associated with a resource, or the capabilities of a server, without implying a resource action or initiating a resource retrieval.¶
Responses to this method are not cacheable.¶
If the OPTIONS request includes an entity-body (as indicated by the presence of Content-Length or Transfer-Encoding), then the media type MUST be indicated by a Content-Type field. Although this specification does not define any use for such a body, future extensions to HTTP might use the OPTIONS body to make more detailed queries on the server. A server that does not support such an extension MAY discard the request body.¶
If the Request-URI is an asterisk ("*"), the OPTIONS request is intended to apply to the server in general rather than to a specific resource. Since a server's communication options typically depend on the resource, the "*" request is only useful as a "ping" or "no-op" type of method; it does nothing beyond allowing the client to test the capabilities of the server. For example, this can be used to test a proxy for HTTP/1.1 compliance (or lack thereof).¶
If the Request-URI is not an asterisk, the OPTIONS request applies only to the options that are available when communicating with that resource.¶
A 200 response SHOULD include any header fields that indicate optional features implemented by the server and applicable to that resource (e.g., Allow), possibly including extensions not defined by this specification. The response body, if any, SHOULD also include information about the communication options. The format for such a body is not defined by this specification, but might be defined by future extensions to HTTP. Content negotiation MAY be used to select the appropriate response format. If no response body is included, the response MUST include a Content-Length field with a field-value of "0".¶
The Max-Forwards request-header field MAY be used to target a specific proxy in the request chain. When a proxy receives an OPTIONS request on an absoluteURI for which request forwarding is permitted, the proxy MUST check for a Max-Forwards field. If the Max-Forwards field-value is zero ("0"), the proxy MUST NOT forward the message; instead, the proxy SHOULD respond with its own communication options. If the Max-Forwards field-value is an integer greater than zero, the proxy MUST decrement the field-value when it forwards the request. If no Max-Forwards field is present in the request, then the forwarded request MUST NOT include a Max-Forwards field.¶
The GET method means retrieve whatever information (in the form of an entity) is identified by the Request-URI. If the Request-URI refers to a data-producing process, it is the produced data which shall be returned as the entity in the response and not the source text of the process, unless that text happens to be the output of the process.¶
The semantics of the GET method change to a "conditional GET" if the request message includes an If-Modified-Since, If-Unmodified-Since, If-Match, If-None-Match, or If-Range header field. A conditional GET method requests that the entity be transferred only under the circumstances described by the conditional header field(s). The conditional GET method is intended to reduce unnecessary network usage by allowing cached entities to be refreshed without requiring multiple requests or transferring data already held by the client.¶
The semantics of the GET method change to a "partial GET" if the request message includes a Range header field. A partial GET requests that only part of the entity be transferred, as described in Section 5.4 of [Part5]. The partial GET method is intended to reduce unnecessary network usage by allowing partially-retrieved entities to be completed without transferring data already held by the client.¶
The response to a GET request is cacheable if and only if it meets the requirements for HTTP caching described in [Part6].¶
See Section 12.2 for security considerations when used for forms.¶
The HEAD method is identical to GET except that the server MUST NOT return a message-body in the response. The metainformation contained in the HTTP headers in response to a HEAD request SHOULD be identical to the information sent in response to a GET request. This method can be used for obtaining metainformation about the entity implied by the request without transferring the entity-body itself. This method is often used for testing hypertext links for validity, accessibility, and recent modification.¶
The response to a HEAD request MAY be cacheable in the sense that the information contained in the response MAY be used to update a previously cached entity from that resource. If the new field values indicate that the cached entity differs from the current entity (as would be indicated by a change in Content-Length, Content-MD5, ETag or Last-Modified), then the cache MUST treat the cache entry as stale.¶
The POST method is used to request that the origin server accept the entity enclosed in the request as data to be processed by the resource identified by the Request-URI in the Request-Line. POST is designed to allow a uniform method to cover the following functions: ¶
The actual function performed by the POST method is determined by the server and is usually dependent on the Request-URI.¶
The action performed by the POST method might not result in a resource that can be identified by a URI. In this case, either 200 (OK) or 204 (No Content) is the appropriate response status, depending on whether or not the response includes an entity that describes the result.¶
If a resource has been created on the origin server, the response SHOULD be 201 (Created) and contain an entity which describes the status of the request and refers to the new resource, and a Location header (see Section 10.4).¶
Responses to this method are not cacheable, unless the response includes appropriate Cache-Control or Expires header fields. However, the 303 (See Other) response can be used to direct the user agent to retrieve a cacheable resource.¶
The PUT method requests that the enclosed entity be stored under the supplied Request-URI. If the Request-URI refers to an already existing resource, the enclosed entity SHOULD be considered as a modified version of the one residing on the origin server. If the Request-URI does not point to an existing resource, and that URI is capable of being defined as a new resource by the requesting user agent, the origin server can create the resource with that URI. If a new resource is created, the origin server MUST inform the user agent via the 201 (Created) response. If an existing resource is modified, either the 200 (OK) or 204 (No Content) response codes SHOULD be sent to indicate successful completion of the request. If the resource could not be created or modified with the Request-URI, an appropriate error response SHOULD be given that reflects the nature of the problem. The recipient of the entity MUST NOT ignore any Content-* (e.g. Content-Range) headers that it does not understand or implement and MUST return a 501 (Not Implemented) response in such cases.¶
If the request passes through a cache and the Request-URI identifies one or more currently cached entities, those entries SHOULD be treated as stale. Responses to this method are not cacheable.¶
The fundamental difference between the POST and PUT requests is reflected in the different meaning of the Request-URI. The URI in a POST request identifies the resource that will handle the enclosed entity. That resource might be a data-accepting process, a gateway to some other protocol, or a separate entity that accepts annotations. In contrast, the URI in a PUT request identifies the entity enclosed with the request -- the user agent knows what URI is intended and the server MUST NOT attempt to apply the request to some other resource. If the server desires that the request be applied to a different URI, it MUST send a 301 (Moved Permanently) response; the user agent MAY then make its own decision regarding whether or not to redirect the request.¶
A single resource MAY be identified by many different URIs. For example, an article might have a URI for identifying "the current version" which is separate from the URI identifying each particular version. In this case, a PUT request on a general URI might result in several other URIs being defined by the origin server.¶
HTTP/1.1 does not define how a PUT method affects the state of an origin server.¶
Unless otherwise specified for a particular entity-header, the entity-headers in the PUT request SHOULD be applied to the resource created or modified by the PUT.¶
The DELETE method requests that the origin server delete the resource identified by the Request-URI. This method MAY be overridden by human intervention (or other means) on the origin server. The client cannot be guaranteed that the operation has been carried out, even if the status code returned from the origin server indicates that the action has been completed successfully. However, the server SHOULD NOT indicate success unless, at the time the response is given, it intends to delete the resource or move it to an inaccessible location.¶
A successful response SHOULD be 200 (OK) if the response includes an entity describing the status, 202 (Accepted) if the action has not yet been enacted, or 204 (No Content) if the action has been enacted but the response does not include an entity.¶
If the request passes through a cache and the Request-URI identifies one or more currently cached entities, those entries SHOULD be treated as stale. Responses to this method are not cacheable.¶
The TRACE method is used to invoke a remote, application-layer loop-back of the request message. The final recipient of the request SHOULD reflect the message received back to the client as the entity-body of a 200 (OK) response. The final recipient is either the origin server or the first proxy or gateway to receive a Max-Forwards value of zero (0) in the request (see Section 10.5). A TRACE request MUST NOT include an entity.¶
TRACE allows the client to see what is being received at the other end of the request chain and use that data for testing or diagnostic information. The value of the Via header field (Section 8.9 of [Part1]) is of particular interest, since it acts as a trace of the request chain. Use of the Max-Forwards header field allows the client to limit the length of the request chain, which is useful for testing a chain of proxies forwarding messages in an infinite loop.¶
If the request is valid, the response SHOULD contain the entire request message in the entity-body, with a Content-Type of "message/http". Responses to this method MUST NOT be cached.¶
Each Status-Code is described below, including a description of which method(s) it can follow and any metainformation required in the response.¶
This class of status code indicates a provisional response, consisting only of the Status-Line and optional headers, and is terminated by an empty line. There are no required headers for this class of status code. Since HTTP/1.0 did not define any 1xx status codes, servers MUST NOT send a 1xx response to an HTTP/1.0 client except under experimental conditions.¶
A client MUST be prepared to accept one or more 1xx status responses prior to a regular response, even if the client does not expect a 100 (Continue) status message. Unexpected 1xx status responses MAY be ignored by a user agent.¶
Proxies MUST forward 1xx responses, unless the connection between the proxy and its client has been closed, or unless the proxy itself requested the generation of the 1xx response. (For example, if a proxy adds a "Expect: 100-continue" field when it forwards a request, then it need not forward the corresponding 100 (Continue) response(s).)¶
The client SHOULD continue with its request. This interim response is used to inform the client that the initial part of the request has been received and has not yet been rejected by the server. The client SHOULD continue by sending the remainder of the request or, if the request has already been completed, ignore this response. The server MUST send a final response after the request has been completed. See Section 7.2.3 of [Part1] for detailed discussion of the use and handling of this status code.¶
The server understands and is willing to comply with the client's request, via the Upgrade message header field (Section 5.4 of [Part5]), for a change in the application protocol being used on this connection. The server will switch protocols to those defined by the response's Upgrade header field immediately after the empty line which terminates the 101 response.¶
The protocol SHOULD be switched only when it is advantageous to do so. For example, switching to a newer version of HTTP is advantageous over older versions, and switching to a real-time, synchronous protocol might be advantageous when delivering resources that use such features.¶
This class of status code indicates that the client's request was successfully received, understood, and accepted.¶
The request has succeeded. The information returned with the response is dependent on the method used in the request, for example: ¶
The request has been fulfilled and resulted in a new resource being created. The newly created resource can be referenced by the URI(s) returned in the entity of the response, with the most specific URI for the resource given by a Location header field. The response SHOULD include an entity containing a list of resource characteristics and location(s) from which the user or user agent can choose the one most appropriate. The entity format is specified by the media type given in the Content-Type header field. The origin server MUST create the resource before returning the 201 status code. If the action cannot be carried out immediately, the server SHOULD respond with 202 (Accepted) response instead.¶
A 201 response MAY contain an ETag response header field indicating the current value of the entity tag for the requested variant just created, see Section 6.1 of [Part4].¶
The request has been accepted for processing, but the processing has not been completed. The request might or might not eventually be acted upon, as it might be disallowed when processing actually takes place. There is no facility for re-sending a status code from an asynchronous operation such as this.¶
The 202 response is intentionally non-committal. Its purpose is to allow a server to accept a request for some other process (perhaps a batch-oriented process that is only run once per day) without requiring that the user agent's connection to the server persist until the process is completed. The entity returned with this response SHOULD include an indication of the request's current status and either a pointer to a status monitor or some estimate of when the user can expect the request to be fulfilled.¶
The returned metainformation in the entity-header is not the definitive set as available from the origin server, but is gathered from a local or a third-party copy. The set presented MAY be a subset or superset of the original version. For example, including local annotation information about the resource might result in a superset of the metainformation known by the origin server. Use of this response code is not required and is only appropriate when the response would otherwise be 200 (OK).¶
The server has fulfilled the request but does not need to return an entity-body, and might want to return updated metainformation. The response MAY include new or updated metainformation in the form of entity-headers, which if present SHOULD be associated with the requested variant.¶
If the client is a user agent, it SHOULD NOT change its document view from that which caused the request to be sent. This response is primarily intended to allow input for actions to take place without causing a change to the user agent's active document view, although any new or updated metainformation SHOULD be applied to the document currently in the user agent's active view.¶
The 204 response MUST NOT include a message-body, and thus is always terminated by the first empty line after the header fields.¶
The server has fulfilled the request and the user agent SHOULD reset the document view which caused the request to be sent. This response is primarily intended to allow input for actions to take place via user input, followed by a clearing of the form in which the input is given so that the user can easily initiate another input action. The response MUST NOT include an entity.¶
This class of status code indicates that further action needs to be taken by the user agent in order to fulfill the request. The action required MAY be carried out by the user agent without interaction with the user if and only if the method used in the second request is GET or HEAD. A client SHOULD detect infinite redirection loops, since such loops generate network traffic for each redirection. ¶
The requested resource corresponds to any one of a set of representations, each with its own specific location, and agent-driven negotiation information (Section 4 of [Part3]) is being provided so that the user (or user agent) can select a preferred representation and redirect its request to that location.¶
Unless it was a HEAD request, the response SHOULD include an entity containing a list of resource characteristics and location(s) from which the user or user agent can choose the one most appropriate. The entity format is specified by the media type given in the Content-Type header field. Depending upon the format and the capabilities of the user agent, selection of the most appropriate choice MAY be performed automatically. However, this specification does not define any standard for such automatic selection.¶
If the server has a preferred choice of representation, it SHOULD include the specific URI for that representation in the Location field; user agents MAY use the Location field value for automatic redirection. This response is cacheable unless indicated otherwise.¶
The requested resource has been assigned a new permanent URI and any future references to this resource SHOULD use one of the returned URIs. Clients with link editing capabilities ought to automatically re-link references to the Request-URI to one or more of the new references returned by the server, where possible. This response is cacheable unless indicated otherwise.¶
The new permanent URI SHOULD be given by the Location field in the response. Unless the request method was HEAD, the entity of the response SHOULD contain a short hypertext note with a hyperlink to the new URI(s).¶
If the 301 status code is received in response to a request method that is known to be "safe", as defined in Section 8.1.1, then the request MAY be automatically redirected by the user agent without confirmation. Otherwise, the user agent MUST NOT automatically redirect the request unless it can be confirmed by the user, since this might change the conditions under which the request was issued. ¶
The requested resource resides temporarily under a different URI. Since the redirection might be altered on occasion, the client SHOULD continue to use the Request-URI for future requests. This response is only cacheable if indicated by a Cache-Control or Expires header field.¶
The temporary URI SHOULD be given by the Location field in the response. Unless the request method was HEAD, the entity of the response SHOULD contain a short hypertext note with a hyperlink to the new URI(s).¶
If the 302 status code is received in response to a request method that is known to be "safe", as defined in Section 8.1.1, then the request MAY be automatically redirected by the user agent without confirmation. Otherwise, the user agent MUST NOT automatically redirect the request unless it can be confirmed by the user, since this might change the conditions under which the request was issued. ¶
The response to the request can be found under a different URI and SHOULD be retrieved using a GET method on that resource. This method exists primarily to allow the output of a POST-activated script to redirect the user agent to a selected resource. The new URI is not a substitute reference for the originally requested resource. The 303 response MUST NOT be cached, but the response to the second (redirected) request might be cacheable.¶
The different URI SHOULD be given by the Location field in the response. Unless the request method was HEAD, the entity of the response SHOULD contain a short hypertext note with a hyperlink to the new URI(s). ¶
The requested resource MUST be accessed through the proxy given by the Location field. The Location field gives the URI of the proxy. The recipient is expected to repeat this single request via the proxy. 305 responses MUST only be generated by origin servers. ¶
The 306 status code was used in a previous version of the specification, is no longer used, and the code is reserved.¶
The requested resource resides temporarily under a different URI. Since the redirection MAY be altered on occasion, the client SHOULD continue to use the Request-URI for future requests. This response is only cacheable if indicated by a Cache-Control or Expires header field.¶
The temporary URI SHOULD be given by the Location field in the response. Unless the request method was HEAD, the entity of the response SHOULD contain a short hypertext note with a hyperlink to the new URI(s) , since many pre-HTTP/1.1 user agents do not understand the 307 status. Therefore, the note SHOULD contain the information necessary for a user to repeat the original request on the new URI.¶
If the 307 status code is received in response to a request method that is known to be "safe", as defined in Section 8.1.1, then the request MAY be automatically redirected by the user agent without confirmation. Otherwise, the user agent MUST NOT automatically redirect the request unless it can be confirmed by the user, since this might change the conditions under which the request was issued.¶
The 4xx class of status code is intended for cases in which the client seems to have erred. Except when responding to a HEAD request, the server SHOULD include an entity containing an explanation of the error situation, and whether it is a temporary or permanent condition. These status codes are applicable to any request method. User agents SHOULD display any included entity to the user.¶
If the client is sending data, a server implementation using TCP SHOULD be careful to ensure that the client acknowledges receipt of the packet(s) containing the response, before the server closes the input connection. If the client continues sending data to the server after the close, the server's TCP stack will send a reset packet to the client, which may erase the client's unacknowledged input buffers before they can be read and interpreted by the HTTP application.¶
The request could not be understood by the server due to malformed syntax. The client SHOULD NOT repeat the request without modifications.¶
This code is reserved for future use.¶
The server understood the request, but is refusing to fulfill it. Authorization will not help and the request SHOULD NOT be repeated. If the request method was not HEAD and the server wishes to make public why the request has not been fulfilled, it SHOULD describe the reason for the refusal in the entity. If the server does not wish to make this information available to the client, the status code 404 (Not Found) can be used instead.¶
The server has not found anything matching the Request-URI. No indication is given of whether the condition is temporary or permanent. The 410 (Gone) status code SHOULD be used if the server knows, through some internally configurable mechanism, that an old resource is permanently unavailable and has no forwarding address. This status code is commonly used when the server does not wish to reveal exactly why the request has been refused, or when no other response is applicable.¶
The method specified in the Request-Line is not allowed for the resource identified by the Request-URI. The response MUST include an Allow header containing a list of valid methods for the requested resource.¶
The resource identified by the request is only capable of generating response entities which have content characteristics not acceptable according to the accept headers sent in the request.¶
Unless it was a HEAD request, the response SHOULD include an entity containing a list of available entity characteristics and location(s) from which the user or user agent can choose the one most appropriate. The entity format is specified by the media type given in the Content-Type header field. Depending upon the format and the capabilities of the user agent, selection of the most appropriate choice MAY be performed automatically. However, this specification does not define any standard for such automatic selection. ¶
If the response could be unacceptable, a user agent SHOULD temporarily stop receipt of more data and query the user for a decision on further actions.¶
The client did not produce a request within the time that the server was prepared to wait. The client MAY repeat the request without modifications at any later time.¶
The request could not be completed due to a conflict with the current state of the resource. This code is only allowed in situations where it is expected that the user might be able to resolve the conflict and resubmit the request. The response body SHOULD include enough information for the user to recognize the source of the conflict. Ideally, the response entity would include enough information for the user or user agent to fix the problem; however, that might not be possible and is not required.¶
Conflicts are most likely to occur in response to a PUT request. For example, if versioning were being used and the entity being PUT included changes to a resource which conflict with those made by an earlier (third-party) request, the server might use the 409 response to indicate that it can't complete the request. In this case, the response entity would likely contain a list of the differences between the two versions in a format defined by the response Content-Type.¶
The requested resource is no longer available at the server and no forwarding address is known. This condition is expected to be considered permanent. Clients with link editing capabilities SHOULD delete references to the Request-URI after user approval. If the server does not know, or has no facility to determine, whether or not the condition is permanent, the status code 404 (Not Found) SHOULD be used instead. This response is cacheable unless indicated otherwise.¶
The 410 response is primarily intended to assist the task of web maintenance by notifying the recipient that the resource is intentionally unavailable and that the server owners desire that remote links to that resource be removed. Such an event is common for limited-time, promotional services and for resources belonging to individuals no longer working at the server's site. It is not necessary to mark all permanently unavailable resources as "gone" or to keep the mark for any length of time -- that is left to the discretion of the server owner.¶
The server refuses to accept the request without a defined Content-Length. The client MAY repeat the request if it adds a valid Content-Length header field containing the length of the message-body in the request message.¶
The server is refusing to process a request because the request entity is larger than the server is willing or able to process. The server MAY close the connection to prevent the client from continuing the request.¶
If the condition is temporary, the server SHOULD include a Retry-After header field to indicate that it is temporary and after what time the client MAY try again.¶
The server is refusing to service the request because the Request-URI is longer than the server is willing to interpret. This rare condition is only likely to occur when a client has improperly converted a POST request to a GET request with long query information, when the client has descended into a URI "black hole" of redirection (e.g., a redirected URI prefix that points to a suffix of itself), or when the server is under attack by a client attempting to exploit security holes present in some servers using fixed-length buffers for reading or manipulating the Request-URI.¶
The server is refusing to service the request because the entity of the request is in a format not supported by the requested resource for the requested method.¶
The request included a Range request-header field (Section 5.4 of [Part5]) and none of the range-specifier values in this field overlap the current extent of the selected resource.¶
The expectation given in an Expect request-header field (see Section 10.2) could not be met by this server, or, if the server is a proxy, the server has unambiguous evidence that the request could not be met by the next-hop server.¶
Response status codes beginning with the digit "5" indicate cases in which the server is aware that it has erred or is incapable of performing the request. Except when responding to a HEAD request, the server SHOULD include an entity containing an explanation of the error situation, and whether it is a temporary or permanent condition. User agents SHOULD display any included entity to the user. These response codes are applicable to any request method.¶
The server encountered an unexpected condition which prevented it from fulfilling the request.¶
The server does not support the functionality required to fulfill the request. This is the appropriate response when the server does not recognize the request method and is not capable of supporting it for any resource.¶
The server, while acting as a gateway or proxy, received an invalid response from the upstream server it accessed in attempting to fulfill the request.¶
The server is currently unable to handle the request due to a temporary overloading or maintenance of the server. The implication is that this is a temporary condition which will be alleviated after some delay. If known, the length of the delay MAY be indicated in a Retry-After header. If no Retry-After is given, the client SHOULD handle the response as it would for a 500 response. ¶
The server, while acting as a gateway or proxy, did not receive a timely response from the upstream server specified by the URI (e.g. HTTP, FTP, LDAP) or some other auxiliary server (e.g. DNS) it needed to access in attempting to complete the request. ¶
The server does not support, or refuses to support, the HTTP protocol version that was used in the request message. The server is indicating that it is unable or unwilling to complete the request using the same major version as the client, as described in Section 3.1 of [Part1], other than with this error message. The response SHOULD contain an entity describing why that version is not supported and what other protocols are supported by that server.¶
This section defines the syntax and semantics of HTTP/1.1 header fields related to request and response semantics.¶
For entity-header fields, both sender and recipient refer to either the client or the server, depending on who sends and who receives the entity.¶
The Allow entity-header field lists the set of methods supported by the resource identified by the Request-URI. The purpose of this field is strictly to inform the recipient of valid methods associated with the resource. An Allow header field MUST be present in a 405 (Method Not Allowed) response.¶
Allow = "Allow" ":" #Method
Example of use:¶
Allow: GET, HEAD, PUT
This field cannot prevent a client from trying other methods. However, the indications given by the Allow header field value SHOULD be followed. The actual set of allowed methods is defined by the origin server at the time of each request.¶
The Allow header field MAY be provided with a PUT request to recommend the methods to be supported by the new or modified resource. The server is not required to support these methods and SHOULD include an Allow header in the response giving the actual supported methods.¶
A proxy MUST NOT modify the Allow header field even if it does not understand all the methods specified, since the user agent might have other means of communicating with the origin server.¶
The Expect request-header field is used to indicate that particular server behaviors are required by the client.¶
Expect = "Expect" ":" 1#expectation expectation = "100-continue" | expectation-extension expectation-extension = token [ "=" ( token | quoted-string ) *expect-params ] expect-params = ";" token [ "=" ( token | quoted-string ) ]
A server that does not understand or is unable to comply with any of the expectation values in the Expect field of a request MUST respond with appropriate error status. The server MUST respond with a 417 (Expectation Failed) status if any of the expectations cannot be met or, if there are other problems with the request, some other 4xx status.¶
This header field is defined with extensible syntax to allow for future extensions. If a server receives a request containing an Expect field that includes an expectation-extension that it does not support, it MUST respond with a 417 (Expectation Failed) status.¶
Comparison of expectation values is case-insensitive for unquoted tokens (including the 100-continue token), and is case-sensitive for quoted-string expectation-extensions.¶
The Expect mechanism is hop-by-hop: that is, an HTTP/1.1 proxy MUST return a 417 (Expectation Failed) status if it receives a request with an expectation that it cannot meet. However, the Expect request-header itself is end-to-end; it MUST be forwarded if the request is forwarded.¶
Many older HTTP/1.0 and HTTP/1.1 applications do not understand the Expect header.¶
See Section 7.2.3 of [Part1] for the use of the 100 (Continue) status.¶
The From request-header field, if given, SHOULD contain an Internet e-mail address for the human user who controls the requesting user agent. The address SHOULD be machine-usable, as defined by "mailbox" in Section 3.4 of [RFC2822]:¶
From = "From" ":" mailbox
An example is:¶
From: email@example.com
This header field MAY be used for logging purposes and as a means for identifying the source of invalid or unwanted requests. It SHOULD NOT be used as an insecure form of access protection. The interpretation of this field is that the request is being performed on behalf of the person given, who accepts responsibility for the method performed. In particular, robot agents SHOULD include this header so that the person responsible for running the robot can be contacted if problems occur on the receiving end.¶
The Internet e-mail address in this field MAY be separate from the Internet host which issued the request. For example, when a request is passed through a proxy the original issuer's address SHOULD be used.¶
The client SHOULD NOT send the From header field without the user's approval, as it might conflict with the user's privacy interests or their site's security policy. It is strongly recommended that the user be able to disable, enable, and modify the value of this field at any time prior to a request.¶
The Location response-header field is used to redirect the recipient to a location other than the Request-URI for completion of the request or identification of a new resource. For 201 (Created) responses, the Location is that of the new resource which was created by the request. For 3xx responses, the location SHOULD indicate the server's preferred URI for automatic redirection to the resource. The field value consists of a single absolute URI.¶
Location = "Location" ":" absoluteURI [ "#" fragment ]
An example is:¶
Location: http://www.example.org/pub/WWW/People.html
There are circumstances in which a fragment identifier in a Location URL would not be appropriate: ¶
The Max-Forwards request-header field provides a mechanism with the TRACE (Section 8.8) and OPTIONS (Section 8.2) methods to limit the number of proxies or gateways that can forward the request to the next inbound server. This can be useful when the client is attempting to trace a request chain which appears to be failing or looping in mid-chain.¶
Max-Forwards = "Max-Forwards" ":" 1*DIGIT
The Max-Forwards value is a decimal integer indicating the remaining number of times this request message may be forwarded.¶
Each proxy or gateway recipient of a TRACE or OPTIONS request containing a Max-Forwards header field MUST check and update its value prior to forwarding the request. If the received value is zero (0), the recipient MUST NOT forward the request; instead, it MUST respond as the final recipient. If the received Max-Forwards value is greater than zero, then the forwarded message MUST contain an updated Max-Forwards field with a value decremented by one (1).¶
The Max-Forwards header field MAY be ignored for all other methods defined by this specification and for any extension methods for which it is not explicitly referred to as part of that method definition.¶
The Referer[sic] request-header field allows the client to specify, for the server's benefit, the address (URI) of the resource from which the Request-URI was obtained (the "referrer", although the header field is misspelled.) The Referer request-header allows a server to generate lists of back-links to resources for interest, logging, optimized caching, etc. It also allows obsolete or mistyped links to be traced for maintenance. The Referer field MUST NOT be sent if the Request-URI was obtained from a source that does not have its own URI, such as input from the user keyboard.¶
Referer = "Referer" ":" ( absoluteURI | relativeURI )
Referer: http://www.example.org/hypertext/Overview.html
If the field value is a relative URI, it SHOULD be interpreted relative to the Request-URI. The URI MUST NOT include a fragment. See Section 12.2 for security considerations.¶
The Retry-After response-header field can be used with a 503 (Service Unavailable) response to indicate how long the service is expected to be unavailable to the requesting client. This field MAY also be used with any 3xx (Redirection) response to indicate the minimum time the user-agent is asked wait before issuing the redirected request. The value of this field can be either an HTTP-date or an integer number of seconds (in decimal) after the time of the response.¶
Retry-After = "Retry-After" ":" ( HTTP-date | delta-seconds )
Two examples of its use are¶
Retry-After: Fri, 31 Dec 1999 23:59:59 GMT Retry-After: 120
In the latter example, the delay is 2 minutes.¶
The Server response-header field contains information about the software used by the origin server to handle the request. The field can contain multiple product tokens (Section 2) and comments identifying the server and any significant subproducts. The product tokens are listed in order of their significance for identifying the application.¶
Server = "Server" ":" 1*( product | comment )
Server: CERN/3.0 libwww/2.17
If the response is being forwarded through a proxy, the proxy application MUST NOT modify the Server response-header. Instead, it MUST include a Via field (as described in Section 8.9 of [Part1]). ¶
The User-Agent request-header field contains information about the user agent originating the request. This is for statistical purposes, the tracing of protocol violations, and automated recognition of user agents for the sake of tailoring responses to avoid particular user agent limitations. User agents SHOULD include this field with requests. The field can contain multiple product tokens (Section 2) and comments identifying the agent and any subproducts which form a significant part of the user agent. By convention, the product tokens are listed in order of their significance for identifying the application.¶
User-Agent = "User-Agent" ":" 1*( product | comment )
User-Agent: CERN-LineMode/2.15 libwww/2.17b3
This section is meant to inform application developers, information providers, and users of the security limitations in HTTP/1.1 as described by this document. The discussion does not include definitive solutions to the problems revealed, though it does make some suggestions for reducing security risks.¶
Like any generic data transfer protocol, HTTP cannot regulate the content of the data that is transferred, nor is there any a priori method of determining the sensitivity of any particular piece of information within the context of any given request. Therefore, applications SHOULD supply as much control over this information as possible to the provider of that information. Four header fields are worth special mention in this context: Server, Via, Referer and From.¶
Revealing the specific software version of the server might allow the server machine to become more vulnerable to attacks against software that is known to contain security holes. Implementors SHOULD make the Server header field a configurable option.¶
Proxies which serve as a portal through a network firewall SHOULD take special precautions regarding the transfer of header information that identifies the hosts behind the firewall. In particular, they SHOULD remove, or replace with sanitized versions, any Via fields generated behind the firewall.¶
The Referer header allows reading patterns to be studied and reverse links drawn. Although it can be very useful, its power can be abused if user details are not separated from the information contained in the Referer. Even when the personal information has been removed, the Referer header might indicate a private document's URI whose publication would be inappropriate.¶
The information sent in the From field might conflict with the user's privacy interests or their site's security policy, and hence it SHOULD NOT be transmitted without the user being able to disable, enable, and modify the contents of the field. The user MUST be able to set the contents of this field within a user preference or application defaults configuration.¶
We suggest, though do not require, that a convenient toggle interface be provided for the user to enable or disable the sending of From and Referer information.¶
The User-Agent (Section 10.9) or Server (Section 10.8) header fields can sometimes be used to determine that a specific client or server have a particular security hole which might be exploited. Unfortunately, this same information is often used for other valuable purposes for which HTTP currently has no better mechanism.¶
Because the source of a link might be private information or might reveal an otherwise private information source, it is strongly recommended that the user be able to select whether or not the Referer field is sent. For example, a browser client could have a toggle switch for browsing openly/anonymously, which would respectively enable/disable the sending of Referer and From information.¶
Clients SHOULD NOT include a Referer header field in a (non-secure) HTTP request if the referring page was transferred with a secure protocol.¶
Authors of services which use the HTTP protocol SHOULD NOT use GET based forms for the submission of sensitive data, because this will cause this data to be encoded in the Request-URI. Many existing servers, proxies, and user agents will log the request URI in some place where it might be visible to third parties. Servers can use POST-based form submission instead¶
If a single server supports multiple organizations that do not trust one another, then it MUST check the values of Location and Content-Location headers in responses that are generated under control of said organizations to make sure that they do not attempt to invalidate resources over which they have no authority.¶
Clarified which error code should be used for inbound server failures (e.g. DNS failures). (Section 9.5.5).¶
201 (Created) had a race that required an Etag be sent when a resource is first created. (Section 9.2.2).¶
Rewrite of message transmission requirements to make it much harder for implementors to get it wrong, as the consequences of errors here can have significant impact on the Internet, and to deal with the following problems: ¶
This change adds the Expect header and 417 status code.¶
Clarify definition of POST. (Section 8.5)¶
Failed to consider that there are many other request methods that are safe to automatically redirect, and further that the user agent is able to make that determination based on the request method semantics. (Sections 9.3.2, 9.3.3 and 9.3.8 )¶
Correct syntax of Location header to allow fragment, as referred symbol wasn't what was expected, and add some clarifications as to when it would not be appropriate. (Section 10.4)¶
In the description of the Server header, the Via field was described as a SHOULD. The requirement was and is stated correctly in the description of the Via header in Section 8.9 of [Part1]. (Section 10.8)¶
Closed issues: ¶
Copyright © The IETF Trust (2008).¶
This document is subject to the rights, licenses and restrictions contained in BCP 78, and except as set forth therein, the authors retain all their rights.¶
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Copies of IPR disclosures made to the IETF Secretariat and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementers or users of this specification can be obtained from the IETF on-line IPR repository at http://www.ietf.org/ipr.¶
The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights that may cover technology that may be required to implement this standard. Please address the information to the IETF at email@example.com.¶


text:
Therefore, in the interest of full disclosure, I hereby list all of the cars that Dr. Grumpy has ever owned:
1982-1983: 1978 Datsun 810 station wagon (if you remember Datsun, you're old, too)
1983: 1979 Pontiac Trans Am (wrecked after 3 months)
1983-1984: 1982 Pontiac Trans Am
1984-1989: 1982 Oldsmobile Cutlass station wagon
1989-1993: 1988 Mercury Cougar
1993-1999: 1990 Infiniti M30
1999 to present: 2000 Nissan Maxima
It should be noted that the current car is the only one I didn't get used. All cars were driven until they were wrecked or completely fell apart, and the cost of repairs exceeded their value.
All cars except the last 3 were shared with siblings and parents. The current one is shared with 3 insane backseat drivers (not including Craig's hair).

subset: commoncrawl


text:
The staff members of Funeral Services Provider will guide your family in creating a meaningful ceremony to honor the life and memory of a loved one. A ceremony can be anything you wish it to be: simple or elaborate, traditional or unique. No matter how it`s tailored, such a ceremony is an important step in recovering from loss.
In this time of sorrow there are decisions to be made; and to honor your loved one you will want to choose what is best. Cremation is an excellent choice. We will guide you through all the processes that are in involved in cremation services. We are family owned with two decades of experience in providing assistance with funeral services and comfort to those who have lost those dear to them.
Veteran Benefits
Burial benefits are available for spouses & dependents buried in a national cemetery include burial with the Veteran, perpetual care, and the spouse or dependents name and date of birth and death will be inscribed on the Veteran`s headstone, at no cost to the family.
Social Security Benefits
A one time payment is payable to the surviving spouse if he or she was living with the beneficiary at the time of death, or in the case that he or she had been living apart, was eligible for Social Security benefits on the beneficiary's earnings record for the month of death.
Scattering at Sea
The popularity of scattering at sea is steadily growing as people look to the organic nature of the ocean to help them bring closure to the loss of a loved one. Scattering at sea combines a sense of finality and a new beginning. It returns us to nature and the origin of our being.
Greening Dameron, MD Funeral Services
As the baby boomers age and the environmentalists among them come to grips with their mortality, the concept of a funeral changes. In Dameron, MD, funeral homes are becoming more aware of a new trend - the green burial or the green funeral. This does not refer to cremation. Instead, it draws upon a preference for reducing the effect a death will have on the physical environment. This includes "Green Burials" occurring without embalming, in simplified caskets (often cardboard or bamboo) and in specialized cemeteries.
While, in Dameron, MD, funeral homes are beginning to address the issues, green burials remain part of the future. Instead, a different approach will help make the entire burial process more environmentally friendly.
Dameron, MD Funeral Services
When it comes to making your or the departed's funeral green, consider your options carefully. Research the topic of green burials and deal with a funeral services provider who is an expert on the subject and on local state legislation.
Once you have done the initial research, talk to a qualified funeral director. They can confirm or refute what you have heard, read or know about the practice in Dameron, MD. Funeral homes are the ideal place to look. They can help you find the way to create the perfect service to meet anyone's needs. They are also aware of what can and cannot be done in the state of Dameron, MD.
Green Burial in Dameron, MD- Restrictions
When it comes to Green Burials, you will find several different restrictions or obstacles can affect upon your decision. These include state, personal and existent.
- State Legislation
Two specific items refer to the anti-green burial practice of embalming. The state requires a body be embalmed if it is to be transported across state lines. This is recorded in Administrative Code Chapter 420-7-1 Vital Statistics Table Of Contents 420-7-1-.01. The state also demands if a body is not to be buried within 36 hours, it must be embalmed. - Personal
Often family members will go against the personal wishes of an individual. No matter what you, he or she write in a will regarding how to dispose of the body, this may NOT be the final say. This is up to the heirs and the executors of the will. Try to make sure everyone is on board with the decision to make the funeral as green as possible. - Existing conditions
Dameron, MD funeral homes may want to help with a green burial, but existing circumstances may restrict the extent of the role they can play. There is a lack of services, specifically a cemetery certified by the GBC.
The Alternative - Greening Dameron, MD Funeral Services
If it is not possible to hold a completely Green Burial, consider making many aspects as environmentally friendly as possible. Talk to several Dameron, MD funeral homes before you decide specifically on the details. Consider the following suggestions as some of the best options possible.
- Funeral Programs: When it comes to designing and printing the programs, look to recycled paper and ink. The same applies to hymn sheets and other related printed material
- Flowers: If you have to have flowers, do not purchase imports or the rare and exotic plants. Stick to local, in-season, organic flowers
- Processions: Rather than form a long, funeral line of single cars containing one or two people, be bold and carpool. This also applies to going from secular or religious location to any other place during the funeral
- Refreshments: If the deceased was a vegetarian, an environmentalist or simply someone who wanted to leave the smallest carbon footprint possible, try to obtain food that reflects this taste. If you want to go completely green, avoid the imported or transported. Make sure all refreshments are organic or, at least, local
A Touch of Green
These are small ways to make large or small Dameron, MD funeral services more environmentally friendly. There are other ways - small and large, to add a touch of green. Dameron, MD funeral homes have often suggested them as a practical measure. In fact, a very common method of remembering loved ones just happens to be green.
Instead of a quarried and carved marble or limestone headstone, why not plant a living or natural memorial. Is a tree not a wonderful way to honour the deceased? If the cemetery does not permit this, ask about a bush or some type of bushy plant. However, be sure to consult with the funeral director, the cemetery officials and a nursery about what will best suit the climate and soil conditions before you make your decision.The Benefits of Greening Dameron, MD Funeral Services
To environmentally minded individuals having as green a burial as possible is their final wish. It is possible. Consult Dameron, MD funeral homes. They can help make this desire a reality.


text:
Dear Mayor Euille and members of City Council,
We are writing to you on behalf of more than 1,500 businesses in Alexandria. We represent businesses of all types and sizes located throughout our great, diverse city, from the West End to Del Ray to Arlandria to Potomac Yard to Old Town to the Eisenhower Corridor and all neighborhoods in between. Our members are business owners, employees and residents many of whom are actively involved in working to make our city a better place to live, work and do business.
The city and our organizations have a common goal: Ramp up economic development in Alexandria to grow our commercial tax base and create a fiscally sound balance of tax revenue generated from commercial and residential properties. The way to accomplish this goal is to attract new businesses and encourage the expansion and retention of existing businesses. We are asking to work even more closely with you to continue transforming the way the city encourages, promotes and serves businesses in Alexandria.
Over a number of years, the city gained a reputation for being an unfriendly place to do business. Complicated, laborious and sometimes backwards processes for starting up a business, including permit and signage applications, unrealistic parking requirements and inadequate customer service have been common complaints we hear from our members.
We most happily acknowledge that the city has made a deliberate effort to improve the procedures necessary to open and expand a business, such as opening a one-stop permitting center, reducing signage fees, allowing more signs to be administratively approved in the historic districts and improving small business zoning regulations at Cameron Station.
We applaud these efforts and fully support continued, aggressive measures to change the perception of Alexandria as being business-unfriendly.
However, we still have a long way to go to compete better with other localities in our region as far as attracting, growing and retaining businesses.
We also acknowledge that we are still facing challenging economic times, including a serious budget deficit for the 2011 fiscal year. We desire to work more closely with you to find creative solutions that will promote economic development, which will benefit Alexandria businesses, our residents and the reputation of our city.
We further acknowledge that you face the additional challenge of having a smaller staff to provide valuable services and we encourage you to educate and empower them to support business owners as valued customers in the same way they support residents. Empowering city staff to make rational, positive decisions should permeate all departments and interactions of the city, resulting in better customer service for businesses, residents and visitors.
Finally, we acknowledge that the Alexandria business community has many voices and unique special interests that can create confusion as to our opinions on certain issues. To better communicate our positions, we pledge to work among ourselves to better coordinate our messages to the city. We now stand united and will speak with one collective voice for business in all parts of Alexandria. Better business in each neighborhood and within specialty industries benefits all of us. We desire to share our best practices and work with the city to implement fair and equitable policies and procedures that will benefit both businesses and residents.
We have selected specific initiatives to pursue in cooperation with you to improve the business climate and create a more positive perception for Alexandria in 2010:
Develop an economically viable small-area plan for the Eisenhower-West corridor.
Clarify and continue to streamline requirements to establish and grow a business in the city particularly for our retail and restaurant establishments.
Acknowledge the contributions of the association community in Alexandria and create incentives to attract and retain them.
Dispel the myth that there is not adequate parking and develop effective strategies to assist people in locating and utilizing existing parking facilities in Old Town; reassess parking requirements for businesses in Del Ray.
Promote businesses in a way that reflects the individual character of each major neighborhood in Alexandria.
Approve a way-finding plan and define requirements to allow businesses to purchase signs as outlined under that plan.
We sincerely wish to partner with you to accomplish each of these initiatives and show clear, measurable results in 2010. We look forward to making positive, long-term changes with you to make Alexandria an even better place to live and for businesses to thrive in 2010 and beyond.
Tina Leone, president and CEO, Alexandria Chamber of Commerce
Cindy McCartney, president, Alexandria Retailers Off King Street
Jill Erber, president,Del Ray Business Association
Felix Oliver, executive director, Eisenhower Partnership
Steve Tees, president, Old Town Business and Professional Association
Bill Reagan, executive director, Small Business Development Center
Scott Kersjes, president, West End Business Association


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A development blog of what Con Kolivas is doing with code at the moment with the emphasis on linux kernel, MuQSS, BFS and -ck.
Sunday 10 April 2011
BFS 400 for 18.104.22.168:
BFS 400 for 220.127.116.11:
2.6.38-ck3 includes BFS 400 (applies to 126.96.36.199):
Ubuntu packages 18.104.22.168-ck2 and 188.8.131.52-ck1 include BFS 400:
Ubuntu Packages
It's been a while in the making, and the advantages of this new BFS are so substantial that they warrant a new version. I was going to announce this on lkml with lots of fanfare, but I see there is still some rare desktop hardware that still is not happy on ondemand governing. SO, my summary is: If you are on a desktop, stick with the performance governor and you'll get significant performance and latency advantages, and if you're on a laptop, you'll find BFS 400 much better than previous iterations with both ondemand and performance governing. There is hard evidence it is better for these. What follows is a long post that I was planning on submitting to lkml, but I'm very wary of burnout. Burnout for me is not to do with being tired of working on the code. No, not at all. The issue is that coding will start intruding too much on my regular life which has absolutely nothing to do with linux kernel and code at all. Once it interferes with my home life, or work, or health, I know it's time to cut back. And that's where I am right now. So instead, here's the post just on the blog:
This is to announce the most major upgrade in the BFS CPU scheduler in a
For those tracking the development on my blog, this is version 0.376 renamed
with mostly cosmetic changes only.
Benchmarks first:
x264 benchmarks on a quad core Xeon X3360 with ondemand (courtesy of Graysky):
Benchmarks on a 4 thread 2 core i7 M620:
Quad core Q9650:
Prescott 3.2GHz Single core HT:
Six core AMD: This has the all important LATENCY and throughput benchmarks.
Each benchmark is the latency with the following loads on a 6 core AMD, make -
j1, j3, j6, j9, j12 and x264 medium and x264 ultrafast (courtesy of Serge Belyshev):
Latency Graphs here:
Sample image from the all important -j6 (where load == number of CPUs):
The BFS cpu scheduler, designed for optimum interactivity and responsiveness
while maintaining excellent throughput on commodity hardware, has been
modified to improve its behaviour on SMP machines, especially when used in
combination with scaling CPU frequency governors (like ondemand), and on
mulitcore hardware that has "turbo" modes. As many distributions are now
setting ondemand as the default governor, even on desktops, and some desktop
GUIs aren't even offering a way to alter the choice of governor any more, it
was clear that I needed to modify BFS to perform optimally with these
Briefly, BFS is a single runqueue design which is used to make the most of the
fact that single runqueues overall have the lowest average latency compared to
separate runqueue designs.
See this youtube link about queuing theory for an interesting parallel with
supermarket checkouts:
Why the other line is likely to move faster
The most consistent feature in BFS to date that was found to improve average
service latency whilst maintaining throughput was that no CPU was ever left to
be idle if there was a task that desired CPU time. Through extensive
experimentation I discovered that it was extremely easy for 4 or more tasks to
desire CPU at once on a virtually idle system. Thus on a quad core, the
average service time would always be lower if the tasks are allowed to move to
the first available idle CPU.
One of the disadvantages of this approach, though, is that although average
service latency is kept low by always using the first available CPU in a
relatively idle system, it means that work never clusters on a CPU. So when a
load-dependent CPU frequency governor is in use, no one CPU is ever seen as
being fully loaded except once the load is great enough for all CPUs to be
loaded. This meant that with BFS, CPUs would not be ramped up to their maximum
speed, and further, the "turbo" modes of newer multicore CPUs were never
engaged since they rely on one core being used while the others are kept idle.
Mainline does not exhibit this problem by virtue of always keeping work local
to each CPU and forcing work elsewhere once some kind of heuristically
determined imbalance was measured and then a rebalance would be forced.
It became apparent that to improve throughput with scaling governors and turbo
CPUs, that I would have to allow CPUs to become idle and service tasks
clustered to less CPUs in order for them to speed up. Trying to find the right
compromise between improving throughput while keeping the service latency low
by allowing a CPU to go idle would require heuristics which I've avoided
greatly to date on BFS. One great concern I have for the mainline scheduler is
the ever-expanding special case treatment of tasks on different architectures
for different one-benchmark workloads that do better, turning our mainline
balancing system into an unmanageable state machine.
Thus I devised a system whereby tasks that are running on a CPU but get
descheduled involuntarily in preference for another task instead of sleeping,
get flagged as "sticky". The reasoning being that if a task had not finished,
then it certainly was going to continue working once rescheduled. Then I added
a cpu_scaling flag which would tell the scheduler that a CPU had been throttled
from its maximum frequency. When one CPU is choosing its next task, if a task
is sticky on another CPU and the current CPU is throttled, it will not take
the task.
This extremely simple technique proved surprisingly good for throughput
without destroying latency. Further investigation revealed the same sticky
system could also be used to determine when to bias against tasks going next
on the local CPU even if the CPU wasn't throttled. So the existing "cache
distance" calculation was removed entirely and tasks that are sticky are just
seen as having soft affinity and biased against. This means that waking tasks
still get very low latency, but sticky tasks are very likely to go back to
their own CPU, while no CPU is left idle if there is work to do, _provided_
the CPU is not throttled.
The existing system for determining which idle CPU to bind to remains
unchanged for it has proven very effective and complementary to this added
So the entire equivalent of a "balancing" mechanism for BFS consists of:
1. Flagging the last CPU bound task that was involuntarily scheduled as being
softly affined to its CPU, and biasing against it on other CPUs.
2. Choosing an idle CPU to wake up based on how busy that core is, and how
close it was to the original CPU it last ran on.
It was discovered the improved throughput meant I was able to further lower
the rr interval such that it is initially set to 6ms regardless of the number
of CPUs, thus improving latency further on SMP.
The resulting change to BFS means throughput with the ondemand CPU frequency
governor is now very close to that of the performance governor, power usage
may be decreased (theoretical, not yet proven), and better throughput and
latency on the performance governor. I would like to point out, however, that
some CPUs were not really designed with ondemand governing in mind,
specifically such as the "extreme" desktop CPUs by Intel. These tend to only
have 2 frequencies, are slow to change from one frequency to another, and may
lie about which CPUs are throttled and actually throttle all of them. Given
how little power saving they really offer, I suggest anyone with a desktop CPU
test for themselves how well it works with ondemand and decide whether they
want to build it into the kernel or not as a way of preventing your
distribution from using the ondemand governor without your knowledge. I detest
the lack of configurability in newer distributions and GUIs, but that's another
In order to quantify the changes in this BFS version, benchmarks were
performed by myself and the help of some other very helpful members of the
community. Thanks to all those who tested along the way and helped it get this
far. The very simple, but reliable and repeatable benchmarks of kbuild at
various jobs and x264 were used to determine the effects on throughput, while
the wakeup-latency app by Jussi Laako was run in the background during the
benchmark as a rough guide to what effect the various loads had on latency.
Again I must stress, the purpose for BFS is to be used as a testing ground for
scheduling to see what can be done when the scheduler is specifically aimed at
commodity hardware for normal desktops and affordable servers. As such, it
should serve as a reference tool to compare to for these workloads and I'm
very pleased to see the uptake of its use actually by the community, and that
mainline is occasionally reminded of the need to keep in touch with this
To the server admins who have contacted me to tell me of their good
experiences with BFS, thank you, but I must stress again that I am unable to
implement extra features like CGROUPS that some of you have asked for. My
time is limited, and my work on the kernel completely unpaid so I can only
direct my attention to areas I personally have interest in.
EDIT: In response to questions from those who haven't been following the progress, yes this BFS is the Brain Fuck Scheduler.
52 comments:
- Ralph Ulrich10 April 2011 at 23:00
It works!
Really only cosmetic changes bfs400 versus bfs376? - Ralph Ulrich10 April 2011 at 23:28
Bingo, I felt:
bfs400 little smoother than bfs376!
Con, you could easily wait a short time to go public for a released 22.214.171.124 to arrive (as usual you mentioned). And adapting bfs400 to cleanly patch the kernel then .... - Anonymous11 April 2011 at 05:28
Hi there. Had a problem while compiling this new version (I use an AUR package with the patches found here)
Got a whole dump of "no space left on device" but I'm pretty sure I have plenty of space here - 500GB HDD with nothing really demanding. What can it be? @anonymous - if you're using the PKGBUILD from the AUR which I maintain, you shouldn't need to be grabbing any files since they're all self contained. As to your no space left of device warning, what RealNC said makes sense.
Why not compile in /dev/shm if you have enough space? Also, you an use pre-compiled binaries from my custom repo. Click my nick here to get linked to the wiki page that has the needed info.- Anonymous11 April 2011 at 13:22
@RealNC - I cleared pacman's cache and it worked on the second try. But I'll take note of that possibility on the future, thanks.
@graysky - no, no, I didn't get anything else here. I just pass by to read some more info. My curiousity is bigger than my actual knowledge at the moment. Anyway, all I use is the PKGBUILD from AUR. Worked like a charm in the first try, and it was the one where I had the most fear - first time I get an "external" kernel.
I don't actually know at the moment such options as compiling in /dev/shm, that's why. Also, thanks for the link, I'll make sure to readay it as well.
Anyway, everything working here again. Thanks a lot, everyone. - Anonymous11 April 2011 at 13:58
Is there a mailing list for -ck discussions? Managed to completely lockup my desktop with patch-2.6.38-ck3 whereas ck1 was stable.
ReplyDelete - karabaja411 April 2011 at 21:07
Hey CK,
thanks for your work! I was wondering is the configuration:
dynamic ticks OFF, preemptive kernel ON, timer 1000HZ, (plus I change generic CPU to Athlon64/Opteron/K8)
still recommended as stated in BFS readme? - VamPiro11 April 2011 at 22:33
AMD 6*3400 MHz (overclock)
10 * game servers
1) ubuntu Natty 2.6.38-8-server_amd64.deb
top = 20-23%
load across multiple cores very uneven. system attempted to load the maximum single-core
2) 184.108.40.206-ck2-1_amd64.deb
top = 14-16%
load almost equally distributed across multiple cores - Ralph Ulrich11 April 2011 at 23:48
ck, thnx very much for
I have reduced Hz_1000 to 300 and disabled dynamic tics. This seemes to be an optimal configuration for a 2009 MacMini core2 64bit Gentoo system:
Looking flash video the MacMini keeps cool at ondemand frequency 1596Mhz with:
I will see if latency keeps being well when compiling ... I diff the 2.6.38-sched-bfs-376.patch and 18.104.22.168-sched-bfs-400.patch. There are just few difference. I use it to make one for opensuse 11.4. It will apply 2.6.37-ck2, bfs363-376-test.patch, and the change from diff above(remove the chage for cpufreq_conservative.c, cpufreq_ondemand.c, cpufreq_userspace.c and add for cpufreq.c). I hope it will be fine.
ReplyDeletevery interesting update to ur scheduler. I have 2 observations....
the first is that on my i7 960 desktop (which uses turbo,and I don't use scaling) I noticed that for whatever reason if I leave dynamic ticks on it does a better job of revving up the frequency over clocking than when I turn it off (I monitor the frequencies with a program called i7z). Also it doesn't seem to take advantage of the hyperthreaded logical cpus like it use to....
I also have a slightly off topic question: how come your ubuntu packaged kernels don't set off the preemptible kernel bug with the fglrx driver. Everytime I compile a preemptible kernel fglrx bugs out in my dmesg@Ralph: Actually you'll see I recommended dynticks ON for a mobile device.
@chronniff: Interesting observation. It may well be that dynticks allows the unused idle threads to go more idle, thus allowing more turbo mode use. Can you confirm with a throughput measurement, rather than a monitor program, that throughput is better with it on? I may revise my recommendations in light of this data. There is actually no reason it wouldn't use hyperthreaded the way it used to so I'm not sure why you say that.
As for the preemptible bug question, perhaps it's just the choice of configuration items. Check the config that is installed with the kernel and compare with your own.OK, everything seems fine. these are the repositories for opensuse.
http://download.opensuse.org/repositories/home:/jingtw:/kernel-11.4/openSUSE_11.4/- Anonymous13 April 2011 at 04:09
Just wondering, why disable cpu frequency scaling ?
Say if i away from keyboard, shouldn't frequency downscaling save power ? CK - two questions:
1) Why disable dynamic ticks?
2) According to the help item for Timer frequency, "the timer interrupt occurs on each processor in an SMP environment leading to NR_CPUS * Hz number of timer interrupts per second."
As I read that, my quad core chip would have a timer frequency 4x higher than what I select. You recommend a setting of 1000 Hz for desktops. Does this mean I need to select 300 Hz for my case (4x300=1,200 Hz)?Hey,
I was trying to figure out what's wrong with that slowed down 2d performance on nvidia cards. bootopper suggested (http://code.google.com/p/chromium/issues/detail?id=71276) to disables and then re-enable HT cores on cpu and it really helped, at least for me. :)
I'm posting this just for your information. :)@graysky: Dynamic ticks adds overhead. The main purpose for dynticks is to reduce power consumption on mobile devices, and it doesn't reduce power by any significant amount on an ordinary desktop, so the added overhead and latency of using it normally isn't worth it. As discussed earlier, though, if you have a turbo enabled CPU, it *might* help it to go turbo more. As for the CPU frequency, no, I mean 1000 absolutely, regardless of the number of CPUs.
@vojta: That's very interesting indeed. I don't have a HT CPU on my desktop, but I'm sure the bugs to do with nvidia slowdown are related.
@anonymous: CPU frequency scaling is not reliably fast to speed up on desktop CPUs (as opposed to mobile CPUs), and desktop CPUs don't throttle very much speed-wise, and the power savings are miniscule compared to the intrinsic ability of the CPU to idle its unused parts. This is all on a desktop CPU. Mobile CPUs are very different. However, nothing is absolute. The newer CPUs are much better in this regard (last year or so).I would be more than happy to benchmark the tickless and non tickless kernels with bfs400 on my i7 960 quad with HT and Turbo mode(v1), just let me know what test to use, should I just time an x264 encoding? I should mention that, despite what I was seeing the other day with i7z, that the system does in fact seem to 'feel' a bit snappier with dynamic ticks turned off
The Hyper Threading thing I metioned is that on previous bfs versions load was always balanced almost perfectly even over all 8 logical cores on my system. But this new release seems to keep all the load of the first four cores (especially the first two), while the remaining logical cores are almost always left idle. After reading your post more thoroughly, I'm guessing this is due to trying to ovverload one cpu while keeping the other threads relatively idle so that the one under load can take advantage of the turbo mode overclocking most effectively since it can hit even higher frequencies if it is just one thread overclocking and a time. The cpu behavior, however, behaves the same as always if I use make -j8 or anything putting the cpu under full load.
(oh yeah, and the fglrx bug in dmesg was just because I had preemptive kernel debugging enabled in the kernel by accident)
After a day of real work everyday use I certainly notice the increase in my systems responsiveness. Thanks again for ur hard work, and congrats on yet another significant improvementThanks chronniff. While it may "appear" to use threads less, that's simply the way the work will be spread out to the cores. Instead of jumping to any free core, it will try to keep the same running thread on the same core. So if your load is only 3 out of 8 threads, the same 3 cores should appear loaded. That's actually an improvement. As for the benchmark, I need something that's actually single threaded to be run on that machine with and without dynticks if possible. The good old kernel build is simple enough. Boot into init 1 (if possible) and go into a clean kernel directory and do:
make clean && make allnoconfig && make -j8 && make clean && time make
with and without dynticks enabled and report the results of the time output please. The make -j8 is just to cache all the files in ram, but the 'make' without jobs will run mostly single threaded, which should invoke turbo mode.
Thanks!- Ralph Ulrich13 April 2011 at 21:02
The overhead of dynticks is why I disabled it and at the same time reduced to Hz_300 for better throughput of my MacMini-2009.
As the discussions make clear there are a lot of possibilities to tune and to get an optimized configuration at the end for your very particular machine ... here is the output for the kernel build test, I booted in into recovery mode in ubuntu, which i believe is supposed to emulate runlevel 1 since ubuntu uses upstart.
cpuinfo (first couple lines):
vendor_id : GenuineIntel
cpu family : 6
model : 26
model name : Intel(R) Core(TM) i7 CPU 960 @ 3.20GHz
stepping : 5
cpu MHz : 3201.000
cache size : 8192 KB
dynamic ticks off:
real 1m26.390s
user 1m17.076s
sys 0m8.056s
dynamic ticks on (tickless):
real 1m23.710s
user 1m13.180s
sys 0m9.012s- Ralph Ulrich15 April 2011 at 00:51
chronniff has better performance with
dynamic ticks on
obviously !
But I don't understand a word:
Shouldn't dynamic have some overhead ? haha, my approach may not have been scientific but I did run the test a second time on each kernel to make sure I was getting consistent data, and each time it was nearly identical. yeah, I think u were right when u said that it enables the threads that aren't in use to stay more idle since they don't have to wakeup as much, and if u look at Intel's in depth explanation of turbo mode, if all threads are active it will overclock all of the cores up to a certain frequency (I think mine is 3.34ghz), but if a single thread is under load while the others stay under a certain frequency, that thread will will be able to overclock even further (I think mine is 3.46).
ReplyDelete- Ralph Ulrich15 April 2011 at 17:52
chronniff, what is the keyword of that cpu capability turbo if you cat /proc/cpuinfo ?
Are these dyntick effects probably also for
Intel core2 duo 2009 (I think without turbo) ? --- linux-2.6.38.orig/kernel/sched_bfs.c 2011-04-15 00:42:27.000000000 +0200
+++ linux-2.6.38/kernel/sched_bfs.c 2011-04-15 00:45:15.521436353 +0200
@@ -1379,8 +1379,8 @@ static void try_preempt(struct task_stru
if (rq_prio < highest_prio)
- if (rq_prio > highest_prio || (rq_prio == highest_prio &&
- deadline_after(rq->rq_deadline, latest_deadline))) {
+ if (rq_prio > highest_prio ||
+ deadline_after(rq->rq_deadline, latest_deadline)) {
latest_deadline = rq->rq_deadline;
highest_prio = rq_prio;
highest_prio_rq = rq;--- linux-2.6.35.orig/kernel/sched_bfs.c 2010-08-31 16:32:43.859976211 +0200
+++ linux-2.6.35/kernel/sched_bfs.c 2010-08-31 16:33:53.943976073 +0200
@@ -129,7 +129,7 @@ int sched_iso_cpu __read_mostly = 70;
* The quota handed out to tasks of all priority levels when refilling their
* time_slice.
-static inline unsigned long timeslice(void)
+static inline int timeslice(void)
return MS_TO_US(rr_interval);
}- Anonymous18 April 2011 at 21:26
I do agree to enable dynamic tick (tickless) to save more power. I think ordinary desktop user (office apps, internet, movies) could benefit from it. Since office apps and internet doesn't use much cpu power. While internet streaming via flash and playing movie can use GPU instead of CPU.
ReplyDelete Hi, as long as we are pasting patches here,
This one might help:
--- linux-126.96.36.199-ck/kernel/sched_bfs.c 2011-04-19 11:47:07.666203441 +0300
+++ linux-2.6.35/kernel/sched_bfs.c 2011-04-19 11:51:54.250203441 +0300
@@ -2754,15 +2754,16 @@
if (idx >= PRIO_LIMIT)
goto out;
queue = grq.queue + idx;
+ if (idx < MAX_RT_PRIO) {
+ /* We found an rt task */
+ edt = list_first_entry(queue, struct task_struct, run_list);
+ goto out_take;
+ }
list_for_each_entry(p, queue, run_list) {
/* Make sure cpu affinity is ok */
if (needs_other_cpu(p, cpu))
- if (idx < MAX_RT_PRIO) {
- /* We found an rt task */
- edt = p;
- goto out_take;
- }
* Soft affinity happens here by not scheduling a task withOh, sorry, I've missed that.
I guess then, a better strategy would be splitting the list_for_each_entry loop into two loops: one for the idx < RT and the rest.
(I don't really know if that will be beneficial at all, that was just something small that bugged me & I thought to share).
Thanks again for your wonderful work on BFS !