MySQL Reference Manual

Optimising the MySQL Server

System/Compile Time and Startup Parameter Tuning

We start with the system-level things since some of these decisions have to be made very early. In other cases a fast look at this part may suffice because it is not that important for the big gains. However, it is always nice to have a feeling about how much one could gain by changing things at this level.

The default OS to use is really important! To get the most use of multiple-CPU machines one should use Solaris (because the threads works really well) or Linux (because the 2.2 kernel has really good SMP support). Also, on 32-bit machines Linux has a 2G file-size limit by default. Hopefully this will be fixed soon when new filesystems are released (XFS/Reiserfs). If you have a desperate need for files bigger than 2G on Linux-Intel 32 bit, you should get the LFS patch for the ext2 filesystem.

Because we have not run MySQL in production on that many platforms, we advise you to test your intended platform before choosing it, if possible.

Other tips:

• If you have enough RAM, you could remove all swap devices. Some operating systems will use a swap device in some contexts even if you have free memory.

• Use the --skip-locking MySQL option to avoid external locking. Note that this will not impact MySQL’s functionality as long as you only run one server. Just remember to take down the server (or lock relevant parts) before you run myisamchk. On some systems this switch is mandatory because the external locking does ...