Subject Re: [firebird-support] Re: Windows 2008 server and Firebird 1.5
Author Helen Borrie
At 06:15 AM 26/03/2009, you wrote:
>That may be, but there are (potential) problems on multi-processor
>machines using SuperServer. So if you use Firebird on a multicore, set
>the CpuAffinityMask to lock SuperServer to one processor, or use Classic.
>
>See http://www.firebirdsql.org/manual/ufb-about-arch.html

CpuAffinity is locked to the first processor (cpu 0) by default (CpuAffinityMask = 1, i.e., 2^0). I guess he could try locking it to *one* other processor instead. This is a bitmask value, so mask is 2 for cpu 1, 4 for cpu 2, 8 for cpu 3, etc. Any values that are not direct exponentials of 2 will give you combinations of multiple cpus, which you DON'T want.

Having hyperthreading enabled can mess up the CpuAffinity, even when it has been properly set to a single cpu, so that's at least a potential problem, too.

./heLen