From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Tue, 24 Jul 2012 10:38:38 -0400
From: Mike Snitzer <snitzer@redhat.com>
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Subject: Re: [linux-lvm] Snapshot limit?
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To: Fred van Zwieten <fvzwieten@vxcompany.com>
Cc: "linux-lvm@redhat.com" <linux-lvm@redhat.com>

On Tue, Jul 24 2012 at 10:21am -0400,
Fred van Zwieten <fvzwieten@vxcompany.com> wrote:

> I agree, but that doesn't answer my questions ;-)

please don't top-post.

The old dm-snapshot cannot scale to 150 concurrent read-only
snaps.. sorry.

There would be a 150-way copy out to the 150 different COW areas.  Aka,
the dm-snapshot N-way copy-out penalty

thinp snapshots use a single shared pool for the COW area.