linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Andrew Morton <akpm@linux-foundation.org>
To: "Huang, Ying" <ying.huang@intel.com>
Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org,
	Arjan Van De Ven <arjan@linux.intel.com>,
	Mel Gorman <mgorman@techsingularity.net>,
	Vlastimil Babka <vbabka@suse.cz>,
	David Hildenbrand <david@redhat.com>,
	Johannes Weiner <jweiner@redhat.com>,
	Dave Hansen <dave.hansen@linux.intel.com>,
	Michal Hocko <mhocko@suse.com>,
	Pavel Tatashin <pasha.tatashin@soleen.com>,
	Matthew Wilcox <willy@infradead.org>,
	Christoph Lameter <cl@linux.com>
Subject: Re: [PATCH 00/10] mm: PCP high auto-tuning
Date: Thu, 21 Sep 2023 08:46:17 -0700	[thread overview]
Message-ID: <20230921084617.b1129a46de247e4a6f0098af@linux-foundation.org> (raw)
In-Reply-To: <87leczwt1o.fsf@yhuang6-desk2.ccr.corp.intel.com>

On Thu, 21 Sep 2023 21:32:35 +0800 "Huang, Ying" <ying.huang@intel.com> wrote:

> >   : It's possible that PCP high auto-tuning doesn't work well for some
> >   : workloads.  So, when PCP high is tuned by hand via the sysctl knob,
> >   : the auto-tuning will be disabled.  The PCP high set by hand will be
> >   : used instead.
> >
> >   Is it a bit hacky to disable autotuning when the user alters
> >   pcp-high?  Would it be cleaner to have a separate on/off knob for
> >   autotuning?
> 
> This was suggested by Mel Gormon,
> 
> https://lore.kernel.org/linux-mm/20230714140710.5xbesq6xguhcbyvi@techsingularity.net/
> 
> "
> I'm not opposed to having an adaptive pcp->high in concept. I think it would
> be best to disable adaptive tuning if percpu_pagelist_high_fraction is set
> though. I expect that users of that tunable are rare and that if it *is*
> used that there is a very good reason for it.
> "
> 
> Do you think that this is reasonable?

I suppose so, if it's documented!

Documentation/admin-guide/sysctl/vm.rst describes
percpu_pagelist_high_fraction.


  reply	other threads:[~2023-09-21 15:46 UTC|newest]

Thread overview: 41+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-09-20  6:18 Huang Ying
2023-09-20  6:18 ` [PATCH 01/10] mm, pcp: avoid to drain PCP when process exit Huang Ying
2023-10-11 12:46   ` Mel Gorman
2023-10-11 17:16     ` Andrew Morton
2023-10-12 13:09       ` Mel Gorman
2023-10-12 13:35         ` Huang, Ying
2023-10-12 12:21     ` Huang, Ying
2023-09-20  6:18 ` [PATCH 02/10] cacheinfo: calculate per-CPU data cache size Huang Ying
2023-09-20  9:24   ` Sudeep Holla
2023-09-22  7:56     ` Huang, Ying
2023-10-11 12:20   ` Mel Gorman
2023-10-12 12:08     ` Huang, Ying
2023-10-12 12:52       ` Mel Gorman
2023-10-12 13:12         ` Huang, Ying
2023-10-12 15:22           ` Mel Gorman
2023-10-13  3:06             ` Huang, Ying
2023-10-16 15:43               ` Mel Gorman
2023-09-20  6:18 ` [PATCH 03/10] mm, pcp: reduce lock contention for draining high-order pages Huang Ying
2023-10-11 12:49   ` Mel Gorman
2023-10-12 12:11     ` Huang, Ying
2023-09-20  6:18 ` [PATCH 04/10] mm: restrict the pcp batch scale factor to avoid too long latency Huang Ying
2023-10-11 12:52   ` Mel Gorman
2023-10-12 12:15     ` Huang, Ying
2023-09-20  6:18 ` [PATCH 05/10] mm, page_alloc: scale the number of pages that are batch allocated Huang Ying
2023-10-11 12:54   ` Mel Gorman
2023-09-20  6:18 ` [PATCH 06/10] mm: add framework for PCP high auto-tuning Huang Ying
2023-09-20  6:18 ` [PATCH 07/10] mm: tune PCP high automatically Huang Ying
2023-09-20  6:18 ` [PATCH 08/10] mm, pcp: decrease PCP high if free pages < high watermark Huang Ying
2023-10-11 13:08   ` Mel Gorman
2023-10-12 12:19     ` Huang, Ying
2023-09-20  6:18 ` [PATCH 09/10] mm, pcp: avoid to reduce PCP high unnecessarily Huang Ying
2023-10-11 14:09   ` Mel Gorman
2023-10-12  7:48     ` Huang, Ying
2023-10-12 12:49       ` Mel Gorman
2023-10-12 13:19         ` Huang, Ying
2023-09-20  6:18 ` [PATCH 10/10] mm, pcp: reduce detecting time of consecutive high order page freeing Huang Ying
2023-09-20 16:41 ` [PATCH 00/10] mm: PCP high auto-tuning Andrew Morton
2023-09-21 13:32   ` Huang, Ying
2023-09-21 15:46     ` Andrew Morton [this message]
2023-09-22  0:33       ` Huang, Ying
2023-10-11 13:05   ` Mel Gorman

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=20230921084617.b1129a46de247e4a6f0098af@linux-foundation.org \
    --to=akpm@linux-foundation.org \
    --cc=arjan@linux.intel.com \
    --cc=cl@linux.com \
    --cc=dave.hansen@linux.intel.com \
    --cc=david@redhat.com \
    --cc=jweiner@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mgorman@techsingularity.net \
    --cc=mhocko@suse.com \
    --cc=pasha.tatashin@soleen.com \
    --cc=vbabka@suse.cz \
    --cc=willy@infradead.org \
    --cc=ying.huang@intel.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