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From: Ling Li <ling@caltech.edu>
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Subject: Re: [linux-lvm] lvm pvscan or vgscan very slow
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Date: Fri Feb 13 18:27:06 2004
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To: linux-lvm@redhat.com

Alasdair G Kergon wrote:
> It shouldn't be that slow!
> Look at your system log and/or run with -vvv to see why it's so slow.

# lvm pvscan -vvv > ~/pvscan-list
# grep "Added to device cache" pvscan-list  | wc -l
   15813

I guess the number of devices to be scanned is just too large (and my 
computer is also a very slow one). Is there some way to specify a 
narrower range of devices to be scanned in LVM2?

> We've a couple of speed-ups that might help (one uses sysfs to reduce
> the number of devices to scan) - they're in the queue of things waiting
> to be checked into CVS after the repository move.
> I'll try to get them imported tomorrow.
This kind of patch will definitely help!

--Ling