All of lore.kernel.org
 help / color / mirror / Atom feed
From: jon ross <jonross@gmail.com>
To: linux-kernel@vger.kernel.org
Subject: VM disk cache behavior.
Date: Tue, 8 Feb 2005 12:06:14 -0500	[thread overview]
Message-ID: <e130a7170502080906596561d7@mail.gmail.com> (raw)

I have an app with a small fixed memory footprint that does a lot of
random reads from a large file. I thought if I added more memory to
the machine the VM would do more caching of the disk, but added memory
does not seem to make any difference. I played with some of the params
in /proc/sys/vm and none of them seem to have any effect.

I tired both a 2.4.20 & 2.6.10 kernels with no difference.

The machine is a Dell 2560. I tired memory configs of 512M, 1G, 4G and
the average read-times do not change.

Do I need to set/compile anything to allow the VM to use the memory?
If is was a way to tell how much memory the VM is using for a drive
cache I could at least tell if my kernel is miss-configured or my app
sucks.

Thanks,

-Jon

             reply	other threads:[~2005-02-08 17:08 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2005-02-08 17:06 jon ross [this message]
2005-02-08 17:18 ` VM disk cache behavior Robert Love
2005-02-08 20:07 ` Chris Wedgwood
2005-02-09  0:37 ` Andy Isaacson
2005-02-09  5:03   ` Kevin Puetz

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=e130a7170502080906596561d7@mail.gmail.com \
    --to=jonross@gmail.com \
    --cc=linux-kernel@vger.kernel.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.