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From: Eric Toombs <ewtoombs@uwaterloo.ca>
To: linux-lvm@redhat.com
Subject: [linux-lvm] faster snapshot creation?
Date: Sat, 22 Feb 2020 06:58:53 -0500	[thread overview]
Message-ID: <d5dd6c06-1e9f-3737-8712-137f92e351cb@uwaterloo.ca> (raw)

Snapshot creation is already pretty fast:

> $ time sudo lvcreate --size 512M --snapshot --name snap /dev/testdbs/template 
>   Logical volume "snap" created.
> 0.03user 0.05system 0:00.46elapsed 18%CPU (0avgtext+0avgdata 28916maxresident)k
> 768inputs+9828outputs (0major+6315minor)pagefaults 0swaps

That's about half a second in real time. But I have a scenario that
would benefit from it being even faster. I'm doing many small unit tests
starting from a template filesystem. I do the snapshot, run the unit
test on the snapshot, then delete the snapshot afterwards using
lvremove. Each unit test, though, takes much less than a second to run
(often on the order of 10ms), so most of the time is being spent making
these snapshots.

So, is there a sort of "dumber" way of making these snapshots, maybe by
changing the allocation algorithm or something?

             reply	other threads:[~2020-02-22 11:58 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-02-22 11:58 Eric Toombs [this message]
2020-02-25  9:31 ` Gionatan Danti
2020-02-25  9:38 ` Zdenek Kabelac
2020-02-25 21:35   ` Eric Toombs
2020-02-26 10:01     ` Zdenek Kabelac
2020-02-26 14:03       ` Douglas Paul
2020-02-26  0:38 ` Stuart D. Gathman

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