From: Michal Hocko <mhocko@suse.cz>
To: Nikolay Borisov <kernel@kyup.com>
Cc: Linux MM <linux-mm@kvack.org>
Subject: Re: Softlockup during memory allocation
Date: Fri, 25 Nov 2016 10:00:22 +0100 [thread overview]
Message-ID: <20161125090022.GA24353@dhcp22.suse.cz> (raw)
In-Reply-To: <a655e607-91c5-173c-ec3a-e211df598f92@kyup.com>
On Thu 24-11-16 15:09:38, Nikolay Borisov wrote:
[...]
> I just checked all the zones for both nodes (the machines have 2 NUMA
> nodes) so essentially there are no reclaimable pages - all are
> anonymous. So the pertinent question is why process are sleeping in
> reclamation path when there are no pages to free. I also observed the
> same behavior on a different node, this time the priority was 0 and the
> code hasn't resorted to OOM. This seems all too strange..
>From my experience we usually hit the memcg OOM quickly if there are no
reclaimable pages. I do not remember anything big changed recently in
that area. Could you enable mm_vmscan_memcg_isolate,
mm_vmscan_memcg_reclaim__{begin,end} and mm_vmscan_lru_shrink_inactive
tracepoints to see what is going on during the reclaim?
I suspect we will see some minor reclaim activity there which will
basically "livelock" the oom from happening but let's see.
--
Michal Hocko
SUSE Labs
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
prev parent reply other threads:[~2016-11-25 9:00 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-11-01 8:12 Nikolay Borisov
2016-11-01 8:16 ` Nikolay Borisov
2016-11-02 19:00 ` Vlastimil Babka
2016-11-04 3:46 ` Hugh Dickins
2016-11-04 12:18 ` Nikolay Borisov
2016-11-13 22:02 ` Nikolay Borisov
2016-11-21 5:31 ` Michal Hocko
2016-11-22 8:56 ` Nikolay Borisov
2016-11-22 14:30 ` Michal Hocko
2016-11-22 14:32 ` Michal Hocko
2016-11-22 14:46 ` Nikolay Borisov
2016-11-22 14:35 ` Nikolay Borisov
2016-11-22 17:02 ` Michal Hocko
2016-11-23 7:44 ` Nikolay Borisov
2016-11-23 7:49 ` Michal Hocko
2016-11-23 7:50 ` Michal Hocko
2016-11-24 11:45 ` Nikolay Borisov
2016-11-24 12:12 ` Michal Hocko
2016-11-24 13:09 ` Nikolay Borisov
2016-11-25 9:00 ` Michal Hocko [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20161125090022.GA24353@dhcp22.suse.cz \
--to=mhocko@suse.cz \
--cc=kernel@kyup.com \
--cc=linux-mm@kvack.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox