linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Shakeel Butt <shakeelb@google.com>
To: Michal Hocko <mhocko@kernel.org>
Cc: Sultan Alsawaf <sultan@kerneltoast.com>,
	Mel Gorman <mgorman@suse.de>,
	 Dave Hansen <dave.hansen@intel.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	 Linux MM <linux-mm@kvack.org>,
	LKML <linux-kernel@vger.kernel.org>,
	 Johannes Weiner <hannes@cmpxchg.org>
Subject: Re: [PATCH] mm: Stop kswapd early when nothing's waiting for it to free pages
Date: Tue, 25 Feb 2020 14:30:03 -0800	[thread overview]
Message-ID: <CALvZod6MW62-+nEw-d0jKxFK9mspOY_tt2JRTDYOrOVyM9_QHw@mail.gmail.com> (raw)
In-Reply-To: <20200225090945.GJ22443@dhcp22.suse.cz>

On Tue, Feb 25, 2020 at 1:10 AM Michal Hocko <mhocko@kernel.org> wrote:
>
[snip]
>
> The proper fix should, however, check the amount of reclaimable pages
> and back off if they cannot meet the target IMO. We cannot rely on the
> general reclaimability here because that could really be thrashing.
>

"check the amount of reclaimable pages" vs "cannot rely on the general
reclaimability"? Can you clarify?

BTW we are seeing a similar situation in our production environment.
We have swappiness=0, no swap from kswapd (because we don't swapout on
pressure, only on cold age) and too few file pages, the kswapd goes
crazy on shrink_slab and spends 100% cpu on it.

Shakeel


  parent reply	other threads:[~2020-02-25 22:30 UTC|newest]

Thread overview: 30+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-02-19 18:25 Sultan Alsawaf
2020-02-19 19:13 ` Dave Hansen
2020-02-19 19:40   ` Sultan Alsawaf
2020-02-19 20:05     ` Michal Hocko
2020-02-19 20:42       ` Sultan Alsawaf
2020-02-19 21:45         ` Mel Gorman
2020-02-19 22:42           ` Sultan Alsawaf
2020-02-20 10:19             ` Mel Gorman
2020-02-21  4:22               ` Sultan Alsawaf
2020-02-21  8:07                 ` Michal Hocko
     [not found]                   ` <20200221210824.GA3605@sultan-book.localdomain>
2020-02-21 21:24                     ` Dave Hansen
2020-02-25  9:09                     ` Michal Hocko
2020-02-25 17:12                       ` Sultan Alsawaf
2020-02-26  9:05                         ` Michal Hocko
2020-02-25 22:30                       ` Shakeel Butt [this message]
2020-02-26  9:08                         ` Michal Hocko
2020-02-26 17:00                           ` Shakeel Butt
2020-02-26 17:41                             ` Michal Hocko
2020-02-26 10:51                       ` Hillf Danton
2020-02-26 17:04                         ` Shakeel Butt
2020-02-27  1:48                         ` Hillf Danton
2020-02-21 18:04                 ` Shakeel Butt
2020-02-21 20:06                   ` Sultan Alsawaf
2020-02-20  8:29         ` Michal Hocko
2020-02-19 19:26 ` Andrew Morton
2020-02-19 22:45   ` Sultan Alsawaf
2020-02-19 19:35 ` Michal Hocko
2020-02-21  4:30 ` [PATCH v2] " Sultan Alsawaf
2020-02-21 18:22   ` Ira Weiny
2020-02-21 20:00     ` Sultan Alsawaf

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=CALvZod6MW62-+nEw-d0jKxFK9mspOY_tt2JRTDYOrOVyM9_QHw@mail.gmail.com \
    --to=shakeelb@google.com \
    --cc=akpm@linux-foundation.org \
    --cc=dave.hansen@intel.com \
    --cc=hannes@cmpxchg.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mgorman@suse.de \
    --cc=mhocko@kernel.org \
    --cc=sultan@kerneltoast.com \
    /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