From: Konstantin Khlebnikov <koct9i@gmail.com>
To: James Hartshorn <jhartshorn@connexity.com>
Cc: "linux-mm@kvack.org" <linux-mm@kvack.org>,
"Kirill A. Shutemov" <kirill@shutemov.name>
Subject: Re: Can we disable transparent hugepages for lack of a legitimate use case please?
Date: Tue, 25 Aug 2015 12:25:29 +0300 [thread overview]
Message-ID: <CALYGNiOg_Zq8Fz-VWskH7LVGdExuq=03+56dpCsDiZ6eAq2A4Q@mail.gmail.com> (raw)
In-Reply-To: <BLUPR02MB1698DD8F0D1550366489DF8CCD620@BLUPR02MB1698.namprd02.prod.outlook.com>
On Mon, Aug 24, 2015 at 11:12 PM, James Hartshorn
<jhartshorn@connexity.com> wrote:
> Hi,
>
>
> I've been struggling with transparent hugepage performance issues, and can't
> seem to find anyone who actually uses it intentionally. Virtually every
> database that runs on linux however recommends disabling it or setting it to
> madvise. I'm referring to:
>
>
> /sys/kernel/mm/transparent_hugepage/enabled
>
>
> I asked on the internet
> http://unix.stackexchange.com/questions/201906/does-anyone-actually-use-and-benefit-from-transparent-huge-pages
> and got no responses there.
>
>
>
> Independently I noticed
>
>
> "sysctl: The scan_unevictable_pages sysctl/node-interface has been disabled
> for lack of a legitimate use case. If you have one, please send an email to
> linux-mm@kvack.org."
>
>
> And thought wow that's exactly what should be done to transparent hugepages.
>
>
> Thoughts?
THP works very well when system has a lot of free memory.
Probably default should be weakened to "only if we have tons of free memory".
For example allocate THP pages atomically, only if buddy allocator already
has huge pages. Also them could be pre-zeroed in background.
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next prev parent reply other threads:[~2015-08-25 9:25 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-08-24 20:12 Can we disable transparent hugepages for lack of a legitimate use case please? James Hartshorn
2015-08-24 20:20 ` Bridgman, John
2015-08-24 20:46 ` James Hartshorn
2015-08-24 23:20 ` Theodore Ts'o
2015-09-10 16:45 ` Andrea Arcangeli
2015-09-10 17:02 ` Andres Freund
2015-09-14 12:37 ` Vlastimil Babka
2015-08-25 9:25 ` Konstantin Khlebnikov [this message]
2015-08-25 9:56 ` Vlastimil Babka
2015-09-01 22:26 ` David Rientjes
2015-09-02 8:55 ` Konstantin Khlebnikov
2015-09-02 9:06 ` Vlastimil Babka
2015-09-09 22:05 ` Andrea Arcangeli
2015-09-03 19:33 ` Andi Kleen
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='CALYGNiOg_Zq8Fz-VWskH7LVGdExuq=03+56dpCsDiZ6eAq2A4Q@mail.gmail.com' \
--to=koct9i@gmail.com \
--cc=jhartshorn@connexity.com \
--cc=kirill@shutemov.name \
--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 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.