From: Tomasz Chmielewski <mangoo@wpkg.org>
To: linux-ide@vger.kernel.org
Subject: strange hdparm results with serverworks and pata-serverworks
Date: Mon, 23 Feb 2009 21:37:21 +0100 [thread overview]
Message-ID: <49A30901.1@wpkg.org> (raw)
I have a ProLiant BL30p G1 machine running Debian Lenny (2.6.26 kernel).
It also has two identical, 2.5 inch WDC WD2500BEVE-00WZT0 IDE drives
(new drives, no smart/badblock errors). Both drives are connected to a
single IDE channel this machine has.
"hdparm -t" gives me different results for these drives: ~10 MB/s for
hda, and ~20 MB/s for hdb with "serverworks" driver on Debian's 2.6.26
kernel.
When using "pata-serverworks" with 2.6.28.7 kernel, hdparm shows the
same results (~10 MB/s for sda, ~20 MB/s for sdb).
However, when I run "dd if=/dev/sda of=/dev/null bs=64k", I can see with
iostat that for the first 7-8 seconds, reads are with ~10 MB/s speed.
Then, reads from sda are with ~20 MB/s or more and are on par with sdb.
Similar dd test for sdb shows that it delivers with speed of ~20 MB/s
from the first second.
Is there an explanation for that?
--
Tomasz Chmielewski
http://wpkg.org
next reply other threads:[~2009-02-23 20:37 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-02-23 20:37 Tomasz Chmielewski [this message]
2009-02-23 20:49 ` strange hdparm results with serverworks and pata-serverworks Greg Freemyer
2009-02-23 22:10 ` Tomasz Chmielewski
2009-02-24 13:29 ` Mark Lord
2009-02-24 18:37 ` Tomasz Chmielewski
2009-02-24 22:39 ` Mark Lord
2009-02-25 9:44 ` Tomasz Chmielewski
2009-02-25 16:26 ` Mark Lord
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