Re: [RFC PATCH 2/3] mm, compaction: use MIN_COMPACT_COSTLY_PRIORITY everywhere for costly orders

From: Vlastimil Babka
Date: Fri Aug 02 2019 - 08:06:02 EST



On 8/1/19 10:33 PM, Mike Kravetz wrote:
> On 8/1/19 6:01 AM, Vlastimil Babka wrote:
>> Could you try testing the patch below instead? It should hopefully
>> eliminate the stalls. If it makes hugepage allocation give up too early,
>> we'll know we have to involve __GFP_RETRY_MAYFAIL in allowing the
>> MIN_COMPACT_PRIORITY priority. Thanks!
>
> Thanks. This patch does eliminate the stalls I was seeing.
>
> In my testing, there is little difference in how many hugetlb pages are
> allocated. It does not appear to be giving up/failing too early. But,
> this is only with __GFP_RETRY_MAYFAIL. The real concern would with THP
> requests. Any suggestions on how to test that?

Here's the full patch, can you include it in your series?
As madvised THP allocations might be affected (hopefully just by stalling less,
not by failing too much), adding relevant people to CC - testing the scenarios
you care about is appreciated. Thanks.

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