FWIW, especially on NUMA machines (like AMDs), physical access to
network resources (such as NICs / HCAs) can be much faster on
specific sockets.
For example, we recently ran some microbenchmarks showing that if you
run 2 MPI processes across 2 NUMA machines (e.g., a simple ping-pong
benc
Hi Jeff,
Jeff Squyres wrote:
I *believe* that this has to do with physical setup within the
machine (i.e., the NIC/HCA bus is physically "closer" to some
sockets), but I'm not much of a hardware guy to know that for sure.
Someone with more specific knowledge should chime in here...
On N
On Dec 2, 2006, at 10:31 AM, Jeff Squyres wrote:
FWIW, especially on NUMA machines (like AMDs), physical access to
network resources (such as NICs / HCAs) can be much faster on
specific sockets.
For example, we recently ran some microbenchmarks showing that if you
run 2 MPI processes across 2 N
On Sat, Dec 02, 2006 at 10:31:30AM -0500, Jeff Squyres wrote:
> FWIW, especially on NUMA machines (like AMDs), physical access to
> network resources (such as NICs / HCAs) can be much faster on
> specific sockets.
Yes, the penalty is actually 50 ns per hop, and you pay it on both
sides. So ou
