Hello,

I am looking for some advice regarding the tuning of a dedicated MySQL
database server.

The machine in questions is a Dell 2850 with dual Xeon procs and 4GB of
memory running FreeBSD 6.1. Its sole purpose in life is to run the
MySQL 5.0.x database engine serving out databases to multiple Apache
servers.

I started with the my-large.cnf file distributed with the MySQL port on
FreeBSD 6.1. I made the following changes:
set max_allowed_packet = 2M
set-variable=max_connections=500

Now the questions:
1. What would be the recommended max_user_connections for the Dell 2850?
2. What is the practical maximum value that max_user_connections could
be set to?

I have been looking around for documentation regarding a max value for
max_user connections and found the following:
[url]http://www-css.fnal.gov/dsg/external/freeware/mysqlTuning.html[/url]

What documentation do others use for tuning MySQL?

My goal is to convert our PHP and Perl applications we run on the Apache
web servers to use persistent database connections to the dedicated
MySQL server.

--
Greg Pelle
System Administrator
Domain-it! Inc.

I highly recommend Jeremy Zawodny's "High Performance MySQL"
from O'Reilly.

Dan

Really you need to look at what your server is doing, the traffic patterns, then you can tune. There is a lot you can determine by
just looking at the output of SHOW STATUS and SHOW VARIABLES.
Threads_created number high and growing? Increase the thread_cache_size variable.
Opened_tables number keeps growing? Increase the table_cache variable

Those are very simple examples and there is a lot more you can tell, including how your indexes are doing. Read up on the status and
variables, there is information on ratios and lots of other good stuff to help you change basic things.

Careful with persistent connections and PHP, you can easily trip over your own connections.

----- Original Message -----
From: "Gregory T Pelle"
To:
Sent: Tuesday, September 12, 2006 12:50 PM
Subject: MySQL tuning advice