From: Avi Kivity <avi@qumranet.com>
To: qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] qcow2 - safe on kill? safe on power fail?
Date: Tue, 22 Jul 2008 17:36:24 +0300 [thread overview]
Message-ID: <4885F068.2060902@qumranet.com> (raw)
In-Reply-To: <4885EA8B.5050908@codemonkey.ws>
Anthony Liguori wrote:
> Avi Kivity wrote:
>> Journalling is so out of fashion. It's better to sequence the
>> operations so that failure results in a leak instead of corruption.
>
> Since the metadata is being updated synchronously, you could probably
> get away with a pretty simple journal. Maybe even a single field that
> contains the offset you are allocating which then gets reset once the
> allocation was completed.
>
>
Why would you want to get away with a simple journal when you can get
away without one?
It's a simple matter of allocating, making sure the allocation is on
disk, and recording that allocation in the tables.
--
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.
next prev parent reply other threads:[~2008-07-22 14:36 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-03-05 21:18 [Qemu-devel] Signal handling and qcow2 image corruption David Barrett
2008-03-05 21:55 ` Anthony Liguori
2008-03-05 23:48 ` David Barrett
2008-03-06 6:57 ` Avi Kivity
2008-07-21 18:10 ` [Qemu-devel] qcow2 - safe on kill? safe on power fail? Jamie Lokier
2008-07-21 19:43 ` Anthony Liguori
2008-07-21 21:26 ` Jamie Lokier
2008-07-21 22:14 ` Anthony Liguori
2008-07-21 23:47 ` Jamie Lokier
2008-07-22 6:06 ` Avi Kivity
2008-07-22 14:08 ` Anthony Liguori
2008-07-22 14:46 ` Jamie Lokier
2008-07-22 19:11 ` Avi Kivity
2008-07-22 14:32 ` Jamie Lokier
2008-07-21 22:00 ` Andreas Schwab
2008-07-21 22:15 ` Anthony Liguori
2008-07-21 22:22 ` David Barrett
2008-07-21 22:50 ` Anthony Liguori
2008-07-22 6:07 ` Avi Kivity
2008-07-22 14:11 ` Anthony Liguori
2008-07-22 14:36 ` Avi Kivity [this message]
2008-07-22 16:16 ` Jamie Lokier
2008-07-22 19:13 ` Avi Kivity
2008-07-22 20:04 ` Jamie Lokier
2008-07-22 21:25 ` Avi Kivity
2008-07-22 14:22 ` Jamie Lokier
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