On 07/15/2013 05:57 PM, Russ Anderson wrote:
On Mon, Jul 15, 2013 at 01:41:05PM -0400, Prarit Bhargava wrote:
> >On 07/15/2013 01:33 PM, "Jóhann B. Guðmundsson" wrote:
>> > >On 07/15/2013 05:21 PM, Prarit Bhargava wrote:
>>> > >>I've done some testing across various systems (both
"large" and "small").
>>> > >>Increasing NR_CPUS seems to have a negligible effect. I see
about a 1.1M
>>> > >>increase in memory usage when switching between 128 cpus and
5120 cpus. Since
>>> > >>most systems ship with 4G or more these days, I cannot see an
issue with
>>> > >>consuming a small amount of memory like this.
>>> > >>
>>> > >>The current NR_CPUS in Fedora is 128 and the current NR_CPUS in
RHEL7 is 5120.
>>> > >>I do not see any reason that those values have to be different
anymore.
>>> > >>
>>> > >>Thoughts/concerns?
>> > >
>> > >I guess the question here is anyone aware of anyone running Fedora with
128
> >
> >Yes - me. And I have HW that exceeds that number.
> >
>> > >cpu's or for that matter 5120.
> >
> >Yes -- Russ, care to share some numbers?
We have a 5120 cpu system: 128 blades, 2 sockets per blade, 10 cores per socket,
2 HyperThreads per core. That system has 8 TB memory.
We have another with 4096 cpus: 128 blades, 2 sockets per blade, 8 cores per
socket, 2 HyperThreads per core. That system has 16 TB memory.
Many smaller ones in the 512-1024 cpu range.
FWIW, RHEL6 is CONFIG_NR_CPUS=4096
And you are currently running Fedora on those systems?
JBG