In the last episode (Jun 19), Chris Johnson said:
> I'm using 3.23.47 on a FreeBSD 4.5 server with two CPUs. I believe I've got
> MySQL configured appropriately to take advantage of this configuration, but
> it appears that it only ever uses one CPU. The other is always idle, or
> running the few remaining Unix processes when they want to do something.
> I've got these lines in my /etc/my.cnf file, for example:
> set-variable = thread_cache=8
> # Try number of CPU's*2 for thread_concurrency
> set-variable = thread_concurrency=4
> Is MySQL unable to use extra CPUs beyond one, am I just confused, or is
> something misconfigured?
FreeBSD's threads library implements threads as a single process, so it
will never use more than one CPU. If you built using the ports tree,
try rebuilding with WITH_LINUXTHREADS=yes, which will use the Linux
threads model (one process per thread).