Hello all,<div><br></div><div>I recently had many teachers and students logging into my site, this is a good thing. The server infrastructure (Linode VPS = 1 load balancer =&gt; 2 webservers and 1 database (DB) server) started to show CPUs that were railing at peaks times on the Munin graphs. This was not so good. The bandaid (which I need to fix) was to add more servers, I now have 5 webservers each have 2GB of RAM and have 2.2.7 GHz CPU (4 of them on each box). This has to be overkill..  Later, realized that MySQL&#39;s system variables were not optimized for the DB server. Ran <a href="https://tools.percona.com/">Percona&#39;s configuration tool</a> along with the <a href="https://github.com/rackerhacker/MySQLTuner-perl">mysqltunner perl script</a>.  This led to the discovery that 32-bit version of Ubuntu will not allow MySQL to use any more that 2GB.</div>

<div><br></div><div>NEW DB server = After upgrading the DB server to 8GB and along with going to 64-bit Ubuntu 10.04, I am <b>still unable to get to the box to use all the memory</b>. The process I&#39;ve been using is (1) use apache bench or jmeter to fling large connections (and long queries) at the DB server (2) run the tuner script to see it&#39;s recommendations to the system variables (2) update the variables, restart mysql and start over.</div>

<div><br></div><div>This has led to unsatisfactory results. I know that fixing the slow queries (which is in process) is a place to start, but I feel that the DB server should be using more RAM. Can someone point out the flaws in my process or maybe even suggest a better way to do this?</div>

<div><br></div><div>Thank you very much for you time.</div><div><br></div><div>First day DBA,</div><div>-Vimal<br><div></div><br>
</div><div>PS Thanks Eric C., for starting me down the right direction.</div>