From mboxrd@z Thu Jan  1 00:00:00 1970
From: Janek Kozicki <janek_listy@wp.pl>
Subject: doesm mdadm try to use fastest HDD ?
Date: Fri, 2 Nov 2007 12:52:05 +0100
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Hello,

My three HHDs have following speeds:

  hda - speed 70 MB/sec
  hdc - speed 27 MB/sec
  sda - speed 60 MB/sec

They create a raid1 /dev/md0 and raid5 /dev/md1 arrays. I wanted to
ask if mdadm is trying to pick the fastest HDD during operation?

Maybe I can "tell" which HDD is preferred?

This came to my mind when I saw this:

  # mdadm --query --detail /dev/md1 | grep Prefer
 
  Preferred Minor : 1

And also in the manual:

  -W, --write-mostly [...] "can be useful if mirroring over a slow link."


many thanks for all your help!
-- 
Janek Kozicki                                                         |