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Date: Wed, 13 Jun 2007 15:05:36 -0400
From: "Leonard Smith" <lrsmith@gmail.com>
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Subject: [linux-lvm] LVM2 resync speed problems
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To: linux-lvm@redhat.com

I am running CentOS4.4 on  two "black" box systems that are
identically configured. Both have 500 GB internal drives, ( same type)
and were installed using the same kickstart configuration. The drives
are being mirrored using LVM.

When I check the first system it is re-syncing and the resync time and speed are

finish=18559.6min speed=355K/sec

On the second system the time and speed are

finish=89.5min speed=68170K/sec

I can't figure out why the speeds are different between the two. I
checked /proc/sys/dev/raid/speed_limit_ and they are the same. The
priority of the md proceses are they same.

I tweaked the setting of the speel_limit_min and increase the nice
priority of the resync process, on the first box, but I could never
get it better than

finish=4551.8min speed=1445K/sec


I've googled and I haven't found much more useful information that to
adjust those settings. Besides those setting what else dictates the
speed used?

Thanks,
Len