amd opteron NUMA support

[Lev Serebryakov]

Hello, Peter.
You wrote 19 ???????? 2008 ?., 18:49:33:

>> Is anyone looking at trying to add specific support for the
>> hyper-transport based numa AMD systems?
>   You don't have to do anything. The penalty for remote access is hidden
> with caching. It's only hugely large working sets that would show the 
> difference, and for those, the memory is probably set up interleaved to
> average out the worst-case behaviour.
  It is not perfectly true. New Java versions have NUMA-aware memory
allocator, which interacts with OS (Solaris is best an linux is much
worse in providin adequate NUMA configuration information to userland)
and this gives about +15% on 4-socket Opteron system and +200% on
SunFire 15K with 72 sockets (of UltraSPARC, so SunFire expirience is
not too releveant for FreeBSD) on typical benchmarks.

-- 
// Black Lion AKA Lev Serebryakov <lev at FreeBSD.org>