From: "Alexander E. Patrakov" <patrakov@gmail.com>
To: "Zdenek Kabelac" <zkabelac@redhat.com>,
"LVM general discussion and development" <linux-lvm@redhat.com>,
"Георгий Бажуков" <g.bazhukov@ideco.ru>
Subject: Re: [linux-lvm] LVM and chain of snapshots
Date: Wed, 20 Jan 2016 18:02:04 +0500 [thread overview]
Message-ID: <569F854C.5070404@gmail.com> (raw)
In-Reply-To: <569F78FA.4050104@redhat.com>
20.01.2016 17:09, Zdenek Kabelac wrote:
> Using lots of old-snaphosts is very bad plan - really time to look at
> thin-provisioning....
> Old-snaps are not going to scale.....
Well, I have already tried using lots of thin snapshots on my PC, in a
context different from what Mark wants. Namely, my snapshots were
created by Snapper, hourly.
Thin snapshots may indeed scale well for reads and writes, but currently
they don't scale at all for the initial activation. The problem is that
"vgchange -ay" and "vgchange -an", by default, run "thin_check", and the
more snapshots I have, the more it takes for "thin_check" to finish.
With 1 snapshot, it is quick enough so that I don't notice. But with,
say, 200 snapshots (some of which include creation of an iso image), it
takes more than 1.5 minutes - more than the initramfs (or myself) is
going to wait during the boot process.
--
Alexander E. Patrakov
next prev parent reply other threads:[~2016-01-20 13:02 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-01-20 10:37 [linux-lvm] LVM and chain of snapshots Марк Коренберг
2016-01-20 12:09 ` Zdenek Kabelac
2016-01-20 12:54 ` Марк Коренберг
2016-01-20 14:20 ` Zdenek Kabelac
2016-01-20 13:02 ` Alexander E. Patrakov [this message]
2016-01-20 13:11 ` Zdenek Kabelac
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=569F854C.5070404@gmail.com \
--to=patrakov@gmail.com \
--cc=g.bazhukov@ideco.ru \
--cc=linux-lvm@redhat.com \
--cc=zkabelac@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).