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System/Compile Time and Startup Parameter Tuning
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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 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 nice) 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
file system.

Because we have not run MySQL in production on that many platforms, we
advice 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 system
     this switch is mandatory because the external locking does not
     work in any case.

     The `--skip-locking' option is on by default when compiling with
     MIT-pthreads, because `flock()' isn't fully supported by
     MIT-pthreads on all platforms.  It's also on default for Linux as
     Linux file locking are not yet safe.

     The only case when you can't use `--skip-locking' is if you run
     multiple MySQL _servers_ (not clients) on the same data, or run
     `myisamchk' on the table without first flushing and locking the
     `mysqld' server tables first.

     You can still use `LOCK TABLES'/`UNLOCK TABLES' even if you are
     using `--skip-locking'