Re: 2.5.38-mm2 dbench $N times

Martin J. Bligh
2002-09-25T20:55:55Z

> Pretty sure each dbench child does it's own write/read to only it's own data.
> There is no sharing that I am aware of between the processes.

Right, but if the processes migrate easily, there's still no CPU locality.
Bill, do you want to try binding 1/32 of the processes to each CPU, and see if
that makes your throughput increase?

> How about running in tmpfs to avoid any disk IO at all?

As far as I understand it, that won't help - we're operating out of pagecache anyway
at this level, I think.

> Also, what's the policy for home node assignment on fork? Are all of these
> children getting the same home node assingnment??

Policy is random - the scheduler lacks any NUMA comprehension at the moment.
The numa sched mods would probably help a lot too.

M.