We're using Amazon's AWS infrastructure. At one time, we did have a load-balanced setup across geographic regions, and our database cluster was divided between those regions. To reduce costs for the time being, and to solve some clustering issues we were having, we cut back to using regions inside the US only. Our latency in other regions is now totally horrible.  Using a CDN for assets (images, files) will satisfy our file-serving needs, but our site is extremely dynamic in nature with pages saving data frequently. This is definitely a First World Problem and one that's come about since the advent of AJAX. Surely, we do not need to re-invent the wheel.  Is using other regions in AWS the only option, and will we have to suck up the less-than-desired database clustering issues? Or... is there a better way?  Also, if we went with distinct architecture in each region, i.e. different database, is there an efficient means to keep data in sync between separate clusters. We're using Percona, for the record.
I host am ExpressionEngine based website on a single Amazon EC2 instance in the US East (Virginia) region. I use Ubuntu.    The website allows members to post their content, and displays it for other members and for users who are not logged in.   Goal: I need to begin serving the same website across the globe, equally fast to Hong Kong, New York, and Los Angeles.   I considered two solutions:  1.Setting up three separate EC2 instances for three regions: Virginia, Oregon, and Singapore. Use Amazon Rot53 Geo Location to direct traffic to instances based on the browser's IP address.   Pro: the website will load fast for the region.   Contra: these will be essentially three separate websites. Unless I am mistaken?   Setting up one instance in a region equally remote from all three locations: (Ireliand), and boost the server to the highest performance available.    Pro: It will be the same website for all regions.   Contra: it will cost a lot to make it fast enough.   My challenges:   a) I do not know a way to sync server settings, database, and content between multiple Ubuntu instances in real time. If a knowledgeable person could explain to me how to do that, I would be most grateful.   b) I am not thoroughly familiar with all Amazon AWS resources. Does AWS has a built-in method that would allow me to achieve my goal of serving a single PHP / MySQL based membership website across the globe equally fast in all three chosen locations?
These may be separate questions, but the following MWE:    \usepackage{pdfpages} ...   \addcontentsline{lot}{subsection}{\ref{tab:UserRoles} \textbf{User Roles}}   \includepdf[pages={-}, pagecommand={\label{tab:UserRoles}}, offset=0in -1in, addtolist={9, table, {The User Roles table}, tab:UserRoles}]{UserRolesTable}   ...   has several unexpected behaviors.   I get the following warning:  Package pdfpages Warning: There's something wrong with the entries of `addtolist'. Not all entries were processed. Check `addtolist' [in the MWE]."    Probably due to the \label not being bound to the inserted pdf (in a table environment), my inserted PDF is numbered using the section, and not the expected "Table X" value.   The manually-inserted LoT line (which also uses the section number rather than the incremented table number) is not formatted like the other lines in the LoT - the number lines up, but the table caption itself is not aligned with the others in the list.   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