[CentOS] NUMA split mode?

Mon Oct 2 11:50:57 UTC 2017
hw <hw at adminart.net>

John R Pierce <pierce at hogranch.com> writes:

> On 10/1/2017 9:10 PM, hw wrote:
>> I´m trying to download the PDF you pointed me to, but the download is
>> stalled.  I´m running Centos 7.4, but perhaps there´s an explanation
>> in the PDF that might tell me what NUMA split mode is supposed to be.
> it loaded fine here again tonight.  huh.

Internet in this country sucks; it´s almost the worst in the world.

> the gist of the article is that they got at best 2-4% improvements
> with RHEL 6/SLES 6 on dual nehalem/westmere  Xeon's when NUMA was
> enabled.  I see no mention of NUMA Split mode

I´ve been able to get the PDF with the tor browser today.

I´d say the gist is that using numad can improve performance, depending
on the hardware used and on the workload it performs.  That, as usual,
leaves everyone to do their own testing with their hardware and their

In my case --- besides using numad, which won´t hurt anything --- it
might be best to use numactl to pin the particular application I want to
tune the most to one node and its memory.  There is more than enough
local memory for it.  In theory, that should give best overall
performance, and the particular application can nothing but benefit from
using local memory.  Since it´s also doing disk I/O, I need to find out
which of the two nodes might be preferable.  Benchmarking would be
really difficult.

However, that still leaves the mystery what NUMA split mode is supposed
to be.

"Didn't work" is an error.