How to optimize Apache and MySQL?

Try to raise mysql wait_timeout in /etc/mysql/my.cnf

Mine is set to 300.

@nfn:

Try to raise mysql wait_timeout in /etc/mysql/my.cnf

Mine is set to 300.
Hi, my MySQL database is not in localhost, it's in another shared hosting. I connected to that database from my Linode.

What is happening is that the MySQL server closes the connection - and when PHP tries to access it again, it fails.

Moving MySQL to localhost will probably solve this. Or, you may want to use this workaround: http://robsnotebook.com/wordpress-mysql-gone-away

@saman007uk:

What is happening is that the MySQL server closes the connection - and when PHP tries to access it again, it fails.

Moving MySQL to localhost will probably solve this.
But at the same time, my other site which uses localhost MySQL was also down. I think there must be something wrong with apache.

@whatness:

I think it's using prefork mpm (dont know how to check that out).
You can do this with the -l option to the Apache server (depending on your system and version, probably either apache2 or httpd).

# apache2 -l
Compiled in modules:
  core.c
  mod_log_config.c
  mod_logio.c
  prefork.c
  http_core.c
  mod_so.c

On Linux, you'll probably see either prefork.c (the default) or worker.c. I think any others are experimental.

@Vance:

You can do this with the -l option to the Apache server (depending on your system and version, probably either apache2 or httpd).
Hi, thanks! It's prefork.c.

For word press, there is a work around: http://robsnotebook.com/wordpress-mysql-gone-away

It basically checks that the persistent connection is working before using it.

Also, this does not have anything to do with Apache directly - it is PHP which connects to the MySQl server through the php5-mysql library, not the Apache server itself.

I use WP Super Cache on my WordPress sites to increase performance, and it has worked really well for me. See the plugin page: http://wordpress.org/extend/plugins/wp-super-cache/

I hope this helps somewhat; the plugin is intended to make sites "Digg-proof." I've withstood a Slashdotting, if that's any indication of its worth.

Try reducing MaxClients to 35. You should see your performance improve dramatically.

Thank you guys. I bought more RAM, and now things get better. Site down again hours ago when the CPU usage jump to about 400%, and I really don't know what was going on at that moment :shock:

cron job?

> Site down again hours ago when the CPU usage jump to about 400%
If you haven't already, install munin (as is posted ad nausium elsewhere ;)).

Or for a quick (?) check, run a cron job every few minutes to append useful stats to a file.

you may want to create a cron script to troublshoot memory/cpu usage. This could be apache/mysql/spamassassin or any other memory demanding application.

Read this first

http://rimuhosting.com/howto/memory.jsp

@refactorial:

Try reducing MaxClients to 35. You should see your performance improve dramatically.
Yay! that works! The site is up for one whole day now.

Oops, now it's down again. Service httpd not running … :cry:

Here's my memory usage. Any ideas? It seems i have to buy more RAM again?

Not to be flip, but I switched to Lighttpd and SQLite for all my web apps. For wordpress, you can hack in SQLite support with http://rathercurious.net/pdo-for-wordpress - I had to manually create tables for a couple WP plugins, but it was worth the effort because I'm seeing a lot better response from my lil Linode 360.

hehe. not to be even more flip, but i dropped wordpress all together and wrote my own lite blogging engine! :) (if you're curious: http://dertyn.com )

you seem to be using way too much memory for what you're doing

did you look "ps aux" of what's going on on your box and what programs exactly are using the memory ?

also, if you don't want to completely replace apache you can consider using nginx as a reverse proxy and have it serve the static pages while you'd keep apache for just the PHP pages.