LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Jeff Davis <linux@j-davis.com>
To: balbir@linux.vnet.ibm.com
Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org
Subject: Re: [PATCH] badness() dramatically overcounts memory
Date: Tue, 05 Feb 2008 15:02:41 -0800	[thread overview]
Message-ID: <1202252561.24634.64.camel@dogma.ljc.laika.com> (raw)
In-Reply-To: <47A7E282.1080902@linux.vnet.ibm.com>

On Tue, 2008-02-05 at 09:43 +0530, Balbir Singh wrote:
> 1. grep on the kernel source tells me that shared_vm is incremented only in
>    vm_stat_account(), which is a NO-OP if CONFIG_PROC_FS is not defined.

I see, thanks for pointing that out. Is there another way do you think?
Would the penalty be to high to enable vm_stat_account when
CONFIG_PROC_FS is not defined?

Or perhaps my patch would only have an effect when CONFIG_PROC_FS is set
(which is default)?

> 2. How have you tested these patches? One way to do it would be to use the
>    memory controller and set a small limit on the control group. A memory
>    intensive application will soon see an OOM.

I have done a quick test a while back when I first wrote the patch. I
will test more thoroughly now.

> The interesting thing is the use of total_vm and not the RSS which is used as
> the basis by the OOM killer. I need to read/understand the code a bit more.

RSS makes more sense to me as well.

To me, it makes no sense to count shared memory, because killing a
process doesn't free the shared memory.

Regards,
	Jeff Davis


  reply	other threads:[~2008-02-05 23:02 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <1202182480.24634.22.camel@dogma.ljc.laika.com>
2008-02-05  4:13 ` Balbir Singh
2008-02-05 23:02   ` Jeff Davis [this message]
2008-02-05 23:09     ` David Rientjes
2008-02-06  1:54       ` KOSAKI Motohiro
2008-02-06  2:05         ` David Rientjes
2008-02-06  4:00         ` Balbir Singh

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=1202252561.24634.64.camel@dogma.ljc.laika.com \
    --to=linux@j-davis.com \
    --cc=balbir@linux.vnet.ibm.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --subject='Re: [PATCH] badness() dramatically overcounts memory' \
    /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

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).