====== Reducing your memory usage ======
===== Preflight =====

  - To see your current memory usage: <code>prstat -Z -s cpu</code>
  - For more ways to check memory usage, see [[check-processes#checking-memory-usage|checking memory usage]].
  - For more useful commands, see [[shell-cheatsheet|the shell cheat-sheet]].




===== Apache & MySQL =====
This information needs to be cleaned up and pulled into the wiki ... for now here are some articles to look through:
  - [[http://discuss.joyent.com/viewtopic.php?id=16413|Joyent forum post on apache memory]]
  - [[http://www.onlamp.com/pub/a/onlamp/2004/02/05/lamp_tuning.html|lamp tuning]]
  - [[http://2bits.com/articles/tuning-the-apache-maxclients-parameter.html|Tuning maxclients]]
  - [[http://emergent.urbanpug.com/?p=60|Optomizing Apache and MySQL for low memory]]

==== Common problems ====
=== Wild card used in Virtualhost entries ===

  - Listen on the specific IP 
    - Good:<code>Listen 1.2.3.4:80</code> <code>Listen 1.2.3.4:443</code>
    - Bad: <code>Listen *</code><code>Listen *:80</code><code>Listen *:443</code>
  - Virtualhost entries
    - Good: <code><VirtualHost 1.2.3.4:80></code>  <code><VirtualHost 1.2.3.4:443></code> 
    - Bad: <code><VirtualHost *:80></code>  <code><VirtualHost *:443></code>

===== Rails Applications =====
[[accelerators:tuning_rails]]


===== Webmin =====


Webmin can optionally be configured to use much less memory (~10MB continuously, and ~50MB peak during complex operations). Edit /etc/webmin/miniserv.conf and comment out the preload= line. This makes Webmin slower on systems that have plenty of memory, but it makes it use a lot less memory most of the time (with all of the normal preload stuff in a complete Virtualmin system it is about 80-90MB continuous with peaks of 110-120MB during complex operations).

preload is a precaching mechanism for some commonly used libraries, primarily used for Virtualmin related modules.

===== Remove unused applications =====
This is a hard one to really give a step by step on.  Only you know what you are using in your stack.  The best way to see is to use <code>svcs -a</code> and see what is what on your machine and start picking through the items.  To remove one thing you use <code> svcadm disable <SOMETHING></code> so for example if you are using PostgreSQL and not MySQL then to remove MySQL from memory you would do this: <code>svcsadm disable cswmysql5</code>