From: Daniel Jordan <daniel.m.jordan@oracle.com>
To: Michal Hocko <mhocko@kernel.org>
Cc: Baptiste Lepers <baptiste.lepers@gmail.com>,
mgorman@techsingularity.net, akpm@linux-foundation.org,
dhowells@redhat.com, linux-mm@kvack.org, hannes@cmpxchg.org
Subject: Re: Lock overhead in shrink_inactive_list / Slow page reclamation
Date: Fri, 11 Jan 2019 09:53:01 -0800 [thread overview]
Message-ID: <20190111175301.csgxlwpbsfecuwug@ca-dmjordan1.us.oracle.com> (raw)
In-Reply-To: <20190111135938.GG14956@dhcp22.suse.cz>
On Fri, Jan 11, 2019 at 02:59:38PM +0100, Michal Hocko wrote:
> On Fri 11-01-19 16:52:17, Baptiste Lepers wrote:
> > Hello,
> >
> > We have a performance issue with the page cache. One of our workload
> > spends more than 50% of it's time in the lru_locks called by
> > shrink_inactive_list in mm/vmscan.c.
>
> Who does contend on the lock? Are there direct reclaimers or is it
> solely kswapd with paths that are faulting the new page cache in?
Yes, and could you please post your performance data showing the time in
lru_lock? Whatever you have is fine, but using perf with -g would give
callstacks and help answer Michal's question about who's contending.
Happy to help profile and debug offline.
next prev parent reply other threads:[~2019-01-11 17:53 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-01-11 5:52 Baptiste Lepers
2019-01-11 13:59 ` Michal Hocko
2019-01-11 17:53 ` Daniel Jordan [this message]
2019-01-13 23:12 ` Baptiste Lepers
2019-01-13 23:12 ` Baptiste Lepers
2019-01-14 7:06 ` Michal Hocko
2019-01-14 7:25 ` Baptiste Lepers
2019-01-14 7:25 ` Baptiste Lepers
2019-01-14 7:44 ` Michal Hocko
2019-01-14 15:22 ` Kirill Tkhai
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=20190111175301.csgxlwpbsfecuwug@ca-dmjordan1.us.oracle.com \
--to=daniel.m.jordan@oracle.com \
--cc=akpm@linux-foundation.org \
--cc=baptiste.lepers@gmail.com \
--cc=dhowells@redhat.com \
--cc=hannes@cmpxchg.org \
--cc=linux-mm@kvack.org \
--cc=mgorman@techsingularity.net \
--cc=mhocko@kernel.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