From: "NeilBrown" <neilb@suse.de>
To: "Mel Gorman" <mgorman@techsingularity.net>
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>,
"Mel Gorman" <mgorman@techsingularity.net>
Subject: Re: [PATCH 6/8] mm/vmscan: Centralise timeout values for reclaim_throttle
Date: Fri, 22 Oct 2021 12:06:13 +1100 [thread overview]
Message-ID: <163486477387.17149.7808824931340167601@noble.neil.brown.name> (raw)
In-Reply-To: <20211019090108.25501-7-mgorman@techsingularity.net>
On Tue, 19 Oct 2021, Mel Gorman wrote:
...
> + switch(reason) {
> + case VMSCAN_THROTTLE_NOPROGRESS:
> + case VMSCAN_THROTTLE_WRITEBACK:
> + timeout = HZ/10;
> +
> + if (atomic_inc_return(&pgdat->nr_writeback_throttled) == 1) {
> + WRITE_ONCE(pgdat->nr_reclaim_start,
> + node_page_state(pgdat, NR_THROTTLED_WRITTEN));
You have introduced a behaviour change that wasn't flagged in the commit
message.
Previously nr_writeback_throttled was only incremented for
VMSCAN_THROTTLE_WRITEBACK, now it is incremented for
VMSCAN_THROTTLE_NOPROGRESS as well.
Some justification would be good.
> + }
> +
> + break;
> + case VMSCAN_THROTTLE_ISOLATED:
> + timeout = HZ/50;
> + break;
> + default:
> + WARN_ON_ONCE(1);
> + timeout = HZ;
> + break;
> }
>
> prepare_to_wait(wqh, &wait, TASK_UNINTERRUPTIBLE);
> ret = schedule_timeout(timeout);
> finish_wait(wqh, &wait);
>
> - if (acct_writeback)
> + if (reason == VMSCAN_THROTTLE_ISOLATED)
(defect) I think you want "!=" there.
While the numbers a still magic, they are now well documented and all in
one place - a definite improvement!
Thanks,
NeilBrown
next prev parent reply other threads:[~2021-10-22 1:06 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 [this message]
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
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 6/8] mm/vmscan: Centralise timeout values for reclaim_throttle 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 6/8] mm/vmscan: Centralise timeout values for reclaim_throttle Mel Gorman
2021-10-14 15:38 ` 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=163486477387.17149.7808824931340167601@noble.neil.brown.name \
--to=neilb@suse.de \
--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=mgorman@techsingularity.net \
--cc=mhocko@suse.com \
--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.