All of lore.kernel.org
 help / color / mirror / Atom feed
From: "Miguel Cabeça" <cabeca@ist.utl.pt>
To: LVM general discussion and development <linux-lvm@redhat.com>
Subject: Re: [linux-lvm] LVM2 seems to chop performance by 33%
Date: Mon, 14 Jun 2004 12:50:34 +0100	[thread overview]
Message-ID: <40CD910A.9040605@ist.utl.pt> (raw)
In-Reply-To: <40C86F52.4090500@dgreaves.com>

Hi,

> I didn't think lvm2 had such a big performance hit?
>
> 65Mb/s on the raid5 device
> 44Mb/s on the lv
>
Did you try to ajust the read ahead with blockdev on the LV itself?

# blockdev --setra XXXX /dev/sda  (raid5 device, just for comparisson)
# blockdev --setra XXXX /dev/vg/lv (lv)

Try some values for the readahead. On my system I use 2048.

Best regards

Miguel Cabe�a

  parent reply	other threads:[~2004-06-14 11:50 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2004-06-10 14:25 [linux-lvm] LVM2 seems to chop performance by 33% David Greaves
2004-06-10 15:05 ` Stuart Harper
2004-06-10 15:31   ` Chris Croswhite
2004-06-10 15:34   ` David Greaves
2004-06-10 16:30     ` Clint Byrum
2004-06-20 18:17       ` David Greaves
2004-06-20 19:53         ` Alasdair G Kergon
2004-06-21  9:55           ` David Greaves
2004-06-14 11:50 ` Miguel Cabeça [this message]
2004-06-14 13:24   ` David Greaves

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=40CD910A.9040605@ist.utl.pt \
    --to=cabeca@ist.utl.pt \
    --cc=linux-lvm@redhat.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 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.