Re: [LKP] [lkp] [xfs] 68a9f5e700: aim7.jobs-per-min -13.6% regression

Michal Hocko
2016-08-19T09:00:21Z

On Thu 18-08-16 15:25:40, Linus Torvalds wrote:
[...]
> So just for testing purposes, you could try changing that
>
> return alloc_pages(gfp, 0);
>
> in __page_cache_alloc() into something like
>
> return alloc_pages_node(cpu_to_node(raw_smp_processor_id())), gfp, 0);

That would break mempolicies AFAICS. Anyway, I might be missing
something (the mempolicy kod has a strange sense for aesthetic) but the
normal case without any explicit mempolicy should use default_policy
which is MPOL_PREFERRED and MPOL_F_LOCAL which means numa_node_id() so
the local node. So the above two should do the same thing unless I have
missing something.
--
Michal Hocko
SUSE Labs