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Date: Tue, 29 Mar 2011 12:48:14 -0500
From: Ray Morris <support@bettercgi.com>
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Subject: Re: [linux-lvm] copy lv from  lv?
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To: linux-lvm@redhat.com

> if lvm do not support lv copy? it is better copy on write.
> dd takes long time.

For a complete copy the only thing faster than "dd" is two 
copies of "dd" piped together. dd is basically limited by
the speed of the physical disks, assuming proper arguments 
to dd.  For a copy on write, that's called a snapshot. LVM 
COULD beused to copy, by making and splitting a mirror, but 
that's going to be a lot slower than dd. (Though a mirror and
split can be used on a live filesystem, wth it unmounted only 
for an instant during the split).
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Ray Morris
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On Tue, 29 Mar 2011 20:53:37 +0800 (CST)
yue <ooolinux@163.com> wrote:

> if lvm do not support lv copy? it is better copy on write.
> dd takes long time.
>  
> thanks