linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Kevin Liu <kevin@potatofrom.space>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: bugzilla-daemon@bugzilla.kernel.org, linux-mm@kvack.org
Subject: Re: [Bug 200627] New: Stutters and high kernel CPU usage from list_lru_count_one when cache fills memory
Date: Mon, 23 Jul 2018 01:52:12 +0000 (UTC)	[thread overview]
Message-ID: <a38b9753-58c5-b128-8d40-abb49f690e4c@potatofrom.space> (raw)
In-Reply-To: <63e10f4d-ad8f-8d02-2f78-caf01eaa72c1@potatofrom.space>

[-- Attachment #1: Type: text/plain, Size: 1442 bytes --]

Correction - after using 4.14.53 for a while, I do actually see
list_lru_count_one at the top, but only at ~10% overhead. The
responsiveness is slightly degraded, but still better than how it was on
4.18-rc4.

On 07/22/2018 08:02 PM, Kevin Liu wrote:
> Sorry, not sure if the previous message registered on bugzilla due to
> the pgp signature? Including it below.
> 
> On 07/22/2018 07:44 PM, Kevin Liu wrote:
>>> How recently?  Were earlier kernels better behaved?
>> I've seen this issue both on Linux 4.16.15 (admittedly using the -ck
>> patchset) and on vanilla Linux 4.18-rc4 (which is what I'm currently using).
>>
>> I'm fairly certain that it did not occur on Linux 4.14.50, which I used
>> previously, but I will boot back into it to double-check and let you know.
>>
> 
> And yes, booted back into Linux 4.14.54, there appears to be no issue --
> list_lru_count_one reaches 6% overhead at most:
> 
> Overhead  Shared Object                     Symbol
> 
>    5.91%  [kernel]                          [k] list_lru_count_one
> 
>    5.13%  [kernel]                          [k] nmi
> 
>    4.08%  [kernel]                          [k] read_hpet
> 
>    1.26%  zma                               [.] Zone::CheckAlarms
> 
>    1.16%  [kernel]                          [k] _raw_spin_lock
> 
>    1.07%  restic                            [.] 0x00000000002e696c
> 
>    1.06%  .perf-wrapped                     [.] hpp__sort_overhead
> 
> 

[-- Attachment #2: Type: text/html, Size: 2231 bytes --]

      reply	other threads:[~2018-07-23  1:52 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <bug-200627-27@https.bugzilla.kernel.org/>
2018-07-22 23:40 ` Andrew Morton
2018-07-22 23:44   ` Kevin Liu
2018-07-23  0:02     ` Kevin Liu
2018-07-23  1:52       ` Kevin Liu [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=a38b9753-58c5-b128-8d40-abb49f690e4c@potatofrom.space \
    --to=kevin@potatofrom.space \
    --cc=akpm@linux-foundation.org \
    --cc=bugzilla-daemon@bugzilla.kernel.org \
    --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