Is it possible to configure Apache Web Server to handle up to 100,000 or more concurrent connections?   I know if this were to be possible, it's definitely going to be resource intensive. In that case, what would be the most likely hardware configuration?  If it's not possible, then what is the maximum concurrent connections that Apache can be configured to handle?  Thanks in advance.
This is a  about capacity planning for web sites. Related:      What are some recommended tools and methods of capacity planning for web sites and web-applications? Please feel free to describe different tools and techniques for different web-servers, frameworks, etc., as well as best-practices that apply to web servers in general.
Find four groups of order 20 not isomorphic to each other. Ubuntu missing from HP boot menu I have a HP laptop with Windows 8.1 and Ubuntu 14.04 dual booted. I used to use F9 key to enter boot menu and chose Ubuntu and then GRUB would appear where I would chose Ubuntu again. This was working fine all this while. Either a hardware change or a Windows update has caused the Ubuntu option to go missing from the boot menu itself.  How do I fix this and boot into Ubuntu again? Where do you go for the 'nearest railroad' in Monopoly? In the American edition of Monopoly, there is a Chance card that says:  Advance token to nearest railroad Pay owner twice the rental to which he/she is entitled. If railroad is unowned, you may buy it from the bank.   However, is this the closest railroad, or the next one? If you are standing on the Chance spot in the light blues, do you go all around the board to Reading, which is the closest to you, or do you go to Pennsylvania, which is the first one you land on? Beamer text and image on the same slide I am new to Beamer and LaTeX itself. Right now, I want to create a simple slide with an image on the right and text and the sidebar (using the Hannover theme) on the left. I cannot figure out how to do that. Any suggestions? C# Equivalent of SQL Server DataTypes For the following SQL Server datatypes, what would be the corresponding datatype in C#?  Exact Numerics  bigint numeric bit smallint decimal smallmoney int tinyint money     Approximate Numerics  float real     Date and Time  date datetimeoffset datetime2 smalldatetime datetime time     Character Strings  char varchar text     Unicode Character Strings  nchar nvarchar ntext     Binary Strings  binary varbinary image     Other Data Types  cursor timestamp hierarchyid uniqueidentifier sql_variant xml table   (source: ) Before I met her I had a poor opinion of her.   As person had a poor opinion before a particular time in past (before He met her) so I think there should be had had.   There are some more example like this:   Before I went to the university, I worked/had worked as a carpenter for 5 years. Before I opened the door, I put/had put the key in the lock. Before I opened the door, I looked/had looked carefully into the barn for snipers.   In all these sentence, for me, it should be perfect tense.  I asked that question on another platform where I was told that if sequence of past event is obvious and sentences uses "before"and "after", we often use past tense. Which means we should use past tense in all these sentences. But I have another sentence "The train had left before I reached the station." If I follow above mentioned rule there should be "left" instead of "had left". But I am damn sure this sentence is correct with "had left".   Am I correct?  Thank you How does the EMH hold onto a phaser while having bullets go through him? In the Voyager episode: "Future's End, Part II" the doctor rescues B'elanna and Chakotay.     PORTER: They've got lasers! A black man and some bald guy.  (The EMH   enters. Porter and Butch's bullets go straight through him.)       PORTER: God in heaven help us.       EMH: Divine intervention is unlikely.  (The EMH phaser stuns them,   then unties Torres and Chakotay.)   In an earlier episode of Voyager, "Phage":     PARIS: But a hologram is just a projection of light held in a magnetic   containment field. There's no real matter involved. (The EMH slaps   Paris.)       EMH: Now, you hit me.  (Paris's hand passes through the EMH's head.)       EMH: The magnetic containment field that creates the illusion of my   body can be modulated to allow matter to pass through it or be   stopped. I might be able to modulate the holographic lungs in the same   way, allowing oxygen and carbon dioxide to pass from the lungs to the   blood stream.   In order to make the above adjustments the doctor had to touch several buttons on a control panel. I realize the time I refer to above he was using the holo-emitter instead.    How does it work exactly that the doctor can have bullets pass straight through him but he's able to hold on to a phaser without it falling out of his hand? Can he simultaneously have part of his body be transparent and the rest be more like matter at the same time? What if the bullets hit the hand holding the phaser? I think one had a shotgun as I recall so there probably would have been pellets going all over the place. Creating Text Elements using ArcPy? Java Constructors I am trying to learn how to specify class constructors in Java. I am starting to understand that they specify the types of instance variables of objects made from that class. They also can be used to set the instance variable initial values. The follow example is from the Java tutorial on Sun's website:  public Bicycle(int startCadence, int startSpeed, int startGear) {     gear = startGear;     cadence = startCadence;     speed = startSpeed; }   Where in your classes source code should you put the constructor(s)?  Are these arguments the names of the variables?: (int startCadence, int startSpeed, int startGear) or are gear, cadence and speed the names of the variables?  What is the difference between (int startCadence, int startSpeed, int startGear) and gear, cadence and speed?  In the unlikely event that my instructor or any administrator from Salt Lake Community College ever comes across this question, let me make my intentions clear. This question is posted in the greatest spirit of academic honesty. I ask this question to seek general advice and help in understanding the proper way to use the Java programming language. I in no way use the work of others and represent it as my own work. I use the answers provided here as a general aid in my understanding. I do all my own work and do not copy work provided by people answering my question. Shoot, Shoot At I have a question about the difference between the verb "shoot" and "shoot at":          Police shot the suspect.     Police shot at the suspect.        Are they just the same? Is product of two closed sets closed? If $A$ is closed in $X$ and $B$ is closed in $Y$,   does it follow that $A \times B$ is closed in $X \times Y$ ? How do I find the location of Python module sources? How do I learn where the source file for a given Python module is installed? Is the method different on Windows than on Linux?  I'm trying to look for the source of the datetime module in particular, but I'm interested in a more general answer as well. I'm looking for an elegant way to show that, among non-negative numbers, $$ \max \{a_1 + b_1, \dots, a_n + b_n\} \leq \max \{a_1, \dots, a_n\} + \max \{b_1, \dots, b_n\} $$  I can show that $\max \{a+b, c+d\} \leq \max \{a,c\} + \max \{b,d\}$ by exhaustively checking all possibilities of orderings among $a,c$ and $b,d$.  But, I feel like there should be a more intuitive/efficient way to show this property for arbitrary sums like the one above. Resizing videos with ffmpeg/avconv to fit into static sized player I have a html 5 video player which is 700px wide, 400px high. I'm trying to use avconv to use ffmpeg to resize (while retaining the aspect ratio) and making sure it fits into my player.  Input can be a file of any size, so I need to resize the larger ones but center the smaller ones with black bars. So far I've tried: -s and -aspect, I've seen pad being used with the -vf switch but don't understand how it works enough to get what I need.    This is a rough idea of what I need. I'm not sure if it's even possible. It's almost like CSS's max-width/max-height. I realise this may just be a jumble of words but if anyone happens to understand what I'm talking about, I'd appreciate help, Thanks.  avconv command:  avconv -y -i control.avi -vcodec libx264 -b 2000k -bufsize 20M -acodec aac -strict experimental -ar 44100 -ab 256k bigbuck_out.mp4 I'm looking for a book that starts with the premise that (once the population size had exceeded a certain number) the future development of mankind (revolutions and wars in so and so many years, colonization of other planets in so and so many years, and so on) could be predicted completely by applied statistics. (IIRC, they used slide rules for those exact predictions, but that is certainly owed to the time the story was written). Next, the predictability was used to take a few tiny measures that would change mankind's fate in a favourable way. After a long time, the predictive system fails(?) because a mutation occurs in some person(s).  And now is the part where I'm not sure if it belongs to this or another story: The mutation results in the ability to "beam" by thinking of a place where one has been before... Ways to put numbered balls in boxes no box being empty I know the formula for putting $n$ identical balls in $r$ different boxes such that each box has at least 1 ball, but what is the formula for putting $n$ different balls in $r$ different boxes, no box being empty?  Thanks! Why are the longer edges being beveled more? How do you sort du -sh /dir/* by size? I read one site that said use | sort -n but that's obviously not right. Here's an example that is wrong.  [~]# du -sh /var/* | sort -n 0       /var/mail 1.2M    /var/www 1.8M    /var/tmp 1.9G    /var/named 2.9M    /var/run 4.1G    /var/log 8.0K    /var/account 8.0K    /var/crash 8.0K    /var/cvs 8.0K    /var/games 8.0K    /var/local 8.0K    /var/nis 8.0K    /var/opt 8.0K    /var/preserve 8.0K    /var/racoon 12K     /var/aquota.user 12K     /var/portsentry 16K     /var/ftp 16K     /var/quota.user 20K     /var/yp 24K     /var/db 28K     /var/empty 32K     /var/lock 84K     /var/profiles 224M    /var/netenberg 235M    /var/cpanel 245M    /var/cache 620M    /var/lib 748K    /var/spool Set margins in maketitle Let $G$ be a finite semi-group with identity such that it has only one idempotent.Is $G$ a group?  It only remains to show that for any $a\in G$ $\exists b\in G$ such that $ab=ba=e$ where $e$ is the identity of $G$  Also $e$ is the only idempotent of $G$ .How to proceed next?