WordPress MU

Hi all,

I've been running my WPMU site from a shared host for the last couple of years but am finally moving to a dedicated server. I'd like to know if anyone would like to share any of the optimisations they have configured on Apache or MySQL, or if you've got any other tips that relate to running your own WPMU-specific server. I currently have about 1000 blogs, so not a huge number but still significant.

Thanks - Stuart.

Well, if you have a good server you won't need many tweaks done for Apache/MySQL/PHP.

If you're planning a rapid extension - from 1k to 10k blogs - then yes, I can share some ideas :)

can I just jump the wagon here?

having one problem with mysql which I can't get rid of:

Connections ø per hour %
max. concurrent connections 9 --- ---
Failed attempts 683 61.94 9.86%
Aborted 0 0.00 0.00%
Total 6,925 628.02 100.00%

any hints where all these failed attempts come from and what to try and debug it?

Otherwise the server is running perfectly. Might be a certain timeout I have set to low?

Just in case the above text is unreadable I am having 9.86% of Failed attempts.

Ovidiu, your mysql log would be helpful :)

It could be something silly like web sessions that close down unexpectedly or even packets that are too big.

Back to the original topic I found a nice little script that analyses your DB and comes back with suggestions for tweaking mySQL's memory usage.

But at the end of the day memory is important for MySQL caches and things like eAccelerator (if you're using it)

@amanzi: If you are going to your own dedicated server, consider something other than Apache (nginx, litespeed, lighttpd) - I always point people (who ask) here :
http://articles.slicehost.com/

Ususally some good tips on setting things up on the server side.

Look here for mysql tips:
http://www.mysqlperformanceblog.com/

for mysql:

check these tools: http://hackmysql.com/MySQLreport and http://wiki.mysqltuner.com/MySQLTuner but both don't give any advice concerning failed connections.

will get back to you with log files.

Well, if you have a good server you won't need many tweaks done for Apache/MySQL/PHP.

Don't let those who provide paid support for MySQL hear you. :)

Thanks for the tools by the way. Haven't seen those before.

This is good too:
http://kb.mediatemple.net/questions/246/(dv)+HOWTO%3A+Basic+Apache+performance+tuning+(httpd)
Applies to any Apache setup.

Also, been playing with Nginx lately. *sweet*

andrea_r: Nginx going on new slice (when I have time to build it), it'll be a good chance to test it against Litespeed - though I will miss a web based configuration system.

@VentureMaker:

what log files would be interesting?
here is an excerpt from my my.cnf:

# * Logging and Replication
#
# Both location gets rotated by the cronjob.
# Be aware that this log type is a performance killer.
#log = /var/log/mysql.log
#log = /var/log/mysql/mysql.log
#
# Error logging goes to syslog. This is a Debian improvement :)
#
# Here you can see queries with especially long duration
log-slow-queries = /var/log/mysql/mysql-slow.log
#
# The following can be used as easy to replay backup logs or for replication.
#server-id = 1
# log-bin = /var/log/mysql/mysql-bin.log
# See /etc/mysql/debian-log-rotate.conf for the number of files kept.
# max_binlog_size = 104857600
#binlog-do-db = include_database_name
#binlog-ignore-db = include_database_name

I have enabled only the slow queries logging. shall I also enable this one:

log = /var/log/mysql.log

? doing a cat /var/log/syslog | grep mysql doesn't show anything.

Ovidiu, slow queries logging should be enabled all the time :) It won't eat many server resources, but it's extremely useful.

And yes, enable mysql.log for some time. It's a 'killer' on a loaded server, but useful to debug your problem with failed attempts.

@VentureMaker
logging has been running for a couple of days now, what should I look for in the log files? They are huge so randomly browsing around is pointless :-(

OK, put them somewhere I can get them from :)

please email me your contact details to ovizii {at} zice [dot] ro

Dropped you a line.

guys, can anyone name some possible reasons for my mysql to have 7.56% Failed attempts?

Connections  	ø per hour  	%
max. concurrent connections 	11 	--- 	---
Failed attempts 	6,989 	61.98 	7.56%
Aborted 	12 	0.00 k 	0.01%
Total 	92 k 	819.58 	100.00%

I tried increasing all timeout and wait variables I might have possibly modified to no avail. I am at a loss. What should I look for in the logs, would there be anything that could point me in the right direction?