From: Mel Gorman <mgorman@techsingularity.net>
To: NeilBrown <neilb@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Theodore Ts'o <tytso@mit.edu>,
Andreas Dilger <adilger.kernel@dilger.ca>,
"Darrick J . Wong" <djwong@kernel.org>,
Matthew Wilcox <willy@infradead.org>,
Michal Hocko <mhocko@suse.com>,
Dave Chinner <david@fromorbit.com>,
Rik van Riel <riel@surriel.com>, Vlastimil Babka <vbabka@suse.cz>,
Johannes Weiner <hannes@cmpxchg.org>,
Jonathan Corbet <corbet@lwn.net>, Linux-MM <linux-mm@kvack.org>,
Linux-fsdevel <linux-fsdevel@vger.kernel.org>,
LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 7/8] mm/vmscan: Increase the timeout if page reclaim is not making progress
Date: Fri, 22 Oct 2021 09:14:50 +0100 [thread overview]
Message-ID: <20211022081450.GH3959@techsingularity.net> (raw)
In-Reply-To: <163486486314.17149.7181265861483962024@noble.neil.brown.name>
On Fri, Oct 22, 2021 at 12:07:43PM +1100, NeilBrown wrote:
> On Tue, 19 Oct 2021, Mel Gorman wrote:
> > Tracing of the stutterp workload showed the following delays
> >
> > 1 usect_delayed=124000 reason=VMSCAN_THROTTLE_NOPROGRESS
> > 1 usect_delayed=128000 reason=VMSCAN_THROTTLE_NOPROGRESS
> > 1 usect_delayed=176000 reason=VMSCAN_THROTTLE_NOPROGRESS
> > 1 usect_delayed=536000 reason=VMSCAN_THROTTLE_NOPROGRESS
> > 1 usect_delayed=544000 reason=VMSCAN_THROTTLE_NOPROGRESS
> > 1 usect_delayed=556000 reason=VMSCAN_THROTTLE_NOPROGRESS
> > 1 usect_delayed=624000 reason=VMSCAN_THROTTLE_NOPROGRESS
> > 1 usect_delayed=716000 reason=VMSCAN_THROTTLE_NOPROGRESS
> > 1 usect_delayed=772000 reason=VMSCAN_THROTTLE_NOPROGRESS
> > 2 usect_delayed=512000 reason=VMSCAN_THROTTLE_NOPROGRESS
> > 16 usect_delayed=120000 reason=VMSCAN_THROTTLE_NOPROGRESS
> > 53 usect_delayed=116000 reason=VMSCAN_THROTTLE_NOPROGRESS
> > 116 usect_delayed=112000 reason=VMSCAN_THROTTLE_NOPROGRESS
> > 5907 usect_delayed=108000 reason=VMSCAN_THROTTLE_NOPROGRESS
> > 71741 usect_delayed=104000 reason=VMSCAN_THROTTLE_NOPROGRESS
> >
> > All the throttling hit the full timeout and then there was wakeup delays
> > meaning that the wakeups are premature as no other reclaimer such as
> > kswapd has made progress. This patch increases the maximum timeout.
>
> Would love to see the comparable tracing results for after the patch.
>
They're in the leader. The trace figures in the changelog are the ones I
had at the time the patch was developed and I didn't keep them up to date
to reduce overall test time. At the last set of results, some throttling
was still hitting the full timeout;
[....]
843 usec_timeout=500000 usect_delayed=12000 reason=VMSCAN_THROTTLE_NOPROGRESS
1299 usec_timeout=500000 usect_delayed=104000 reason=VMSCAN_THROTTLE_NOPROGRESS
2839 usec_timeout=500000 usect_delayed=8000 reason=VMSCAN_THROTTLE_NOPROGRESS
10111 usec_timeout=500000 usect_delayed=4000 reason=VMSCAN_THROTTLE_NOPROGRESS
21492 usec_timeout=500000 usect_delayed=0 reason=VMSCAN_THROTTLE_NOPROGRESS
36441 usec_timeout=500000 usect_delayed=500000 reason=VMSCAN_THROTTLE_NOPROGRESS
--
Mel Gorman
SUSE Labs
next prev parent reply other threads:[~2021-10-22 8:14 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-10-19 9:01 [PATCH v4 0/8] Remove dependency on congestion_wait in mm/ Mel Gorman
2021-10-19 9:01 ` [PATCH 1/8] mm/vmscan: Throttle reclaim until some writeback completes if congested Mel Gorman
2021-10-19 9:01 ` [PATCH 2/8] mm/vmscan: Throttle reclaim and compaction when too may pages are isolated Mel Gorman
2021-10-19 17:12 ` Yang Shi
2021-10-19 9:01 ` [PATCH 3/8] mm/vmscan: Throttle reclaim when no progress is being made Mel Gorman
2021-10-19 9:01 ` [PATCH 4/8] mm/writeback: Throttle based on page writeback instead of congestion Mel Gorman
2021-10-19 9:01 ` [PATCH 5/8] mm/page_alloc: Remove the throttling logic from the page allocator Mel Gorman
2021-10-19 9:20 ` Vlastimil Babka
2021-10-19 9:01 ` [PATCH 6/8] mm/vmscan: Centralise timeout values for reclaim_throttle Mel Gorman
2021-10-22 1:06 ` NeilBrown
2021-10-22 8:12 ` Mel Gorman
2021-10-19 9:01 ` [PATCH 7/8] mm/vmscan: Increase the timeout if page reclaim is not making progress Mel Gorman
2021-10-22 1:07 ` NeilBrown
2021-10-22 8:14 ` Mel Gorman [this message]
2021-10-19 9:01 ` [PATCH 8/8] mm/vmscan: Delay waking of tasks throttled on NOPROGRESS Mel Gorman
2021-10-19 22:00 ` [PATCH v4 0/8] Remove dependency on congestion_wait in mm/ Andrew Morton
2021-10-20 8:44 ` Mel Gorman
2021-10-22 1:15 ` NeilBrown
2021-10-22 8:39 ` Mel Gorman
2021-10-22 11:26 ` NeilBrown
2021-10-22 13:17 ` Mel Gorman
2021-10-27 0:43 ` NeilBrown
2021-10-27 10:13 ` Mel Gorman
-- strict thread matches above, loose matches on Subject: below --
2021-10-22 14:46 [PATCH v5 " Mel Gorman
2021-10-22 14:46 ` [PATCH 7/8] mm/vmscan: Increase the timeout if page reclaim is not making progress Mel Gorman
2021-10-08 13:53 [PATCH v3 0/8] Remove dependency on congestion_wait in mm/ Mel Gorman
2021-10-08 13:53 ` [PATCH 7/8] mm/vmscan: Increase the timeout if page reclaim is not making progress Mel Gorman
2021-10-14 15:39 ` Vlastimil Babka
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=20211022081450.GH3959@techsingularity.net \
--to=mgorman@techsingularity.net \
--cc=adilger.kernel@dilger.ca \
--cc=akpm@linux-foundation.org \
--cc=corbet@lwn.net \
--cc=david@fromorbit.com \
--cc=djwong@kernel.org \
--cc=hannes@cmpxchg.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mhocko@suse.com \
--cc=neilb@suse.de \
--cc=riel@surriel.com \
--cc=tytso@mit.edu \
--cc=vbabka@suse.cz \
--cc=willy@infradead.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.