From: Anshuman Khandual <anshuman.khandual@arm.com>
To: John Hubbard <jhubbard@nvidia.com>,
Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: linux-mm@kvack.org, hughd@google.com,
Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>,
Zi Yan <ziy@nvidia.com>,
Andrew Morton <akpm@linux-foundation.org>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm/vmstat: Add events for PMD based THP migration without split
Date: Tue, 2 Jun 2020 11:00:37 +0530 [thread overview]
Message-ID: <f88603c5-f9ce-115d-1976-3b0e7558777e@arm.com> (raw)
In-Reply-To: <274be3bf-2206-5e98-8114-1d91fac472c9@nvidia.com>
On 06/02/2020 10:18 AM, John Hubbard wrote:
> On 2020-06-01 21:20, Anshuman Khandual wrote:
> ...
>>> also important: maybe this patch should also be tracking other causes
>>> of THP PMD migration failure, in order to get a truer accounting of the
>>> situation.
>
> I hope one of the experts here can weigh in on that...
>
>> Is there any other failure reasons which are only specific to THP migration.
>> Else, adding stats about generic migration failure reasons will just blur
>> the overall understanding about THP migration successes and failure cases
>> that results in splitting.
>>
>
> Thinking about that: we do have PGMIGRATE_SUCCESS and PGMIGRATE_FAIL, so I
> suppose comparing those numbers with the new THP_PMD_MIGRATION_SUCCESS and
> THP_PMD_MIGRATION_FAILURE events should cover it.
That is right.
>
> However, the fact that this is under discussion hints at the need for a
> bit of documentation help. What do you think about adding some notes about
> all of this to, say, Documentation/vm/page_migration.rst ?
Sure but probably bit later. Because I am also planning to add couple of
trace events for THP migration, hence will update the documentation part
for both VM stat and trace events together.
next prev parent reply other threads:[~2020-06-02 5:31 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-05-22 3:34 [PATCH] mm/vmstat: Add events for PMD based THP migration without split Anshuman Khandual
2020-06-01 16:57 ` Daniel Jordan
2020-06-02 3:20 ` John Hubbard
2020-06-02 4:20 ` Anshuman Khandual
2020-06-02 4:48 ` John Hubbard
2020-06-02 5:30 ` Anshuman Khandual [this message]
2020-06-02 14:52 ` Daniel Jordan
2020-06-03 4:36 ` Anshuman Khandual
2020-06-03 16:08 ` Daniel Jordan
2020-06-02 15:01 ` Matthew Wilcox
2020-06-03 1:26 ` Anshuman Khandual
2020-06-03 2:57 ` Matthew Wilcox
2020-06-03 4:58 ` Anshuman Khandual
2020-06-03 11:09 ` Matthew Wilcox
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=f88603c5-f9ce-115d-1976-3b0e7558777e@arm.com \
--to=anshuman.khandual@arm.com \
--cc=akpm@linux-foundation.org \
--cc=daniel.m.jordan@oracle.com \
--cc=hughd@google.com \
--cc=jhubbard@nvidia.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=n-horiguchi@ah.jp.nec.com \
--cc=ziy@nvidia.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;
as well as URLs for NNTP newsgroup(s).