Re: NUMA settings

On Tue, 2020-05-05 at 07:56 +0200, Marc Rechté wrote:
> Thanks for answers. Further readings make me think that we should *not*
> start postgres with numactl --interleave=all: this may have counter
> productive effect on backends anon memory (heap, stack). IMHO, what is
> important is to use Huge Pages for shared buffers: they are allocated
> (reserved) by the kernel at boot time and spread evenly on all nodes. On
> top of that they never swap.
>
> My (temp) conclusions are following:
> vm.zone_reclaim_mode = 0
> kernel.numa_balancing = 0 (still not sure with that choice)
> wm.swappiness = 60 (default)
> start postgres as usual (no numactl)

Thanks for sharing your insights.

I think that "vm.swappiness" should be 0.
PostgreSQL does its own memory management, any swapping by the kernel
would go against that.

Yours,
Laurenz Albe
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