There are no rules. Google's servers are typically two cores with 4GB. They prefer numbers to iron per server. One can always trade cache for CPU and disk IO. On one of my servers, query_cache_size = 256M, eliminated prunes and got me an 8:1 hit to insert ratio. You might experiment to find that number for your system. I have never seen any convincing evidence that running your MySQL server on a separate host compensates for the transit time between hosts. Of course queries that reduce are kinder to bandpass than inner joins. I run much Drupal and I am not convinced the code is efficient. The relational algebra required to join columns implemented as tables (to enable flexible (user defined) schemas) is horrendus. Intimacy with your server will result in awareness. Jim <div class="gmail_quote">On Tue, Aug 11, 2009 at 3:39 PM, Mark van Harmelen <<a href="mailto:markvanharmelen@gmail.com">markvanharmelen@gmail.com</a>> wrote: <blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">Hi everyone On Mon, Aug 10, 2009 at 11:06 PM, Hakan Koseoglu <<a href="mailto:hakan@koseoglu.org">hakan@koseoglu.org</a>> wrote: > .... 4GB of RAM is not much <div class="im">> for a busy database application </div>Are there any rules of thumb or formulae for a good performant RAM size (per core?) for a busy data base server, mySQL is the database in question. In this scenario, the web app, for a strongly web 2.0 social networking service, is running on different servers and making requests of the db server. Sorry if this is a terrible question, no sizing information makes it hard to answer. Given the lack of information, is the answer something algorithmic, like "start at x GB / core, look at the paging behaviour, and if there is paging, then increase the memory size until any paging tails off" ? If this is the kind of answer, anyone care to hazard a guess at x? thanks mark <div><div></div><div class="h5"> -- ubuntu-server mailing list <a href="mailto:ubuntu-server@lists.ubuntu.com">ubuntu-server@lists.ubuntu.com</a> <a href="https://lists.ubuntu.com/mailman/listinfo/ubuntu-server" target="_blank">https://lists.ubuntu.com/mailman/listinfo/ubuntu-server</a> More info: <a href="https://wiki.ubuntu.com/ServerTeam" target="_blank">https://wiki.ubuntu.com/ServerTeam</a> </div></div></blockquote></div> -- <a href="http://ls.net">http://ls.net</a> <a href="http://drupal.ls.net">http://drupal.ls.net</a> The path to God starts with a simple act of kindness.