2.4.22 + RAID 1 + SATA + 2 disks => no maximum speed
From: Catalin BOIE
Date: Fri Sep 05 2003 - 00:04:14 EST
Hi!
I have a machine with 2 SATA disks on 2 separate buses.
hdparm -t /dev/hda reports 50MB/s
hdparm -t /dev/hdb reports 50MB/s
I created a raid1 array with hda3 and hdc3, same partition sizes.
If I do hdparm -t /dev/md0 it reports 50MB/s
If I do cat /dev/md0 > /dev/null, vmstat reports 50MB/s
If I start another cat /dev/md0 > /dev/null, in another console, I get
100MB/s from vmstat.
Why I don't get 100MB/s on a single cat command?
Some other test:
cat /dev/hda3 > /dev/null&
cat /dev/hdc3 > /dev/null&
vmstat shows 100MB/s.
Also, seems that writing is very slow (8MB/s).
Any ideas?
Thank you very much!
---
Catalin(ux) BOIE
catab@xxxxxxxxxxxxxxx
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