Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1410233

Re: [RFC 03/13] mm, page_alloc: don't retry initial attempt in slowpath

From Vlastimil Babka <vbabka@suse.cz>
Newsgroups linux.kernel
Subject Re: [RFC 03/13] mm, page_alloc: don't retry initial attempt in slowpath
Date 2016-05-31 14:10 +0200
Message-ID <rEQEH-2x9-53@gated-at.bofh.it> (permalink)
References <rxaqR-6fU-5@gated-at.bofh.it> <rxaKd-6py-3@gated-at.bofh.it> <rELlG-7d7-79@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


On 05/31/2016 08:25 AM, Joonsoo Kim wrote:
> On Tue, May 10, 2016 at 09:35:53AM +0200, Vlastimil Babka wrote:
>> After __alloc_pages_slowpath() sets up new alloc_flags and wakes up kswapd, it
>> first tries get_page_from_freelist() with the new alloc_flags, as it may
>> succeed e.g. due to using min watermark instead of low watermark. This attempt
>> does not have to be retried on each loop, since direct reclaim, direct
>> compaction and oom call get_page_from_freelist() themselves.
>
> Hmm... there is a corner case. If did_some_progress is 0 or compaction
> is deferred, get_page_from_freelist() isn't called. But, we can
> succeed to allocate memory since there is a kswapd that reclaims
> memory in background.

Hmm good point. I think the cleanest solution is to let 
__alloc_pages_direct_reclaim attempt regardless of did_some_progress.

> Thanks.
>

Back to linux.kernel | Previous | NextPrevious in thread | Find similar | Unroll thread


Thread

Re: [RFC 03/13] mm, page_alloc: don't retry initial attempt in  slowpath Joonsoo Kim <iamjoonsoo.kim@lge.com> - 2016-05-31 08:30 +0200
  Re: [RFC 03/13] mm, page_alloc: don't retry initial attempt in  slowpath Vlastimil Babka <vbabka@suse.cz> - 2016-05-31 14:10 +0200

csiph-web