From: Jamie Lokier <jamie@shareable.org>
To: Kevin Wolf <kwolf@redhat.com>
Cc: QEMU Developers <qemu-devel@nongnu.org>, Christoph Hellwig <hch@lst.de>
Subject: Re: [Qemu-devel] [PATCH] Add new block driver for the VDI format (use aio)
Date: Mon, 27 Jul 2009 10:23:19 +0100 [thread overview]
Message-ID: <20090727092319.GA7967@shareable.org> (raw)
In-Reply-To: <4A6D5EA2.2080706@redhat.com>
Kevin Wolf wrote:
> Though I guess that for static images typically not only metadata is
> preallocated, but zeros are written for the whole disk content? Maybe we
> could implement a three-way flag like preallocate=[no,metadata,data] and
> let qemu-img handle the data part (writing zeros is the same for all
> formats and would even work with raw).
Note that you can also preallocate space with posix_fallocate(), which
fills the file with zeros but (sometimes) doesn't take as long as
writing zeros.
Apparently it is almost essential when writing large files in small
pieces on Windows, and on Linux it is supported by the ext4
filesystem, but I haven't checked either claim.
-- Jamie
next prev parent reply other threads:[~2009-07-27 9:23 UTC|newest]
Thread overview: 44+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-07-03 19:24 [Qemu-devel] [PATCH] RFC: Add new block driver for the VDI format Stefan Weil
2009-07-03 19:29 ` [Qemu-devel] [PATCH] Check availability of uuid header / lib Stefan Weil
2009-07-03 19:29 ` [Qemu-devel] [PATCH] Add new block driver for the VDI format Stefan Weil
2009-07-05 8:05 ` Christoph Hellwig
2009-07-05 14:02 ` Stefan Weil
2009-07-06 10:25 ` Christoph Hellwig
2009-07-06 17:19 ` Stefan Weil
2009-07-05 14:44 ` Kevin Wolf
2009-07-06 13:37 ` [Qemu-devel] [PATCH] RFC: " Anthony Liguori
2009-07-06 21:10 ` Stefan Weil
2009-07-06 21:28 ` Anthony Liguori
2009-07-07 7:55 ` Kevin Wolf
2009-07-07 9:04 ` Jamie Lokier
2009-07-07 10:30 ` Christoph Hellwig
2009-07-07 10:33 ` Kevin Wolf
2009-08-02 14:27 ` Avi Kivity
2009-08-03 2:25 ` Anthony Liguori
2009-08-03 13:02 ` Avi Kivity
2009-08-03 15:20 ` Christoph Hellwig
2009-07-23 15:58 ` [Qemu-devel] [PATCH] RFC: Add new block driver for the VDI format (aio version) Stefan Weil
2009-07-23 20:27 ` [Qemu-devel] [PATCH] Check availability of uuid header / lib Stefan Weil
2009-07-24 6:32 ` Christoph Egger
2009-10-01 18:13 ` Stefan Weil
2009-10-02 8:32 ` Christoph Egger
2009-10-01 18:10 ` [Qemu-devel] [PATCH] Check availability of uuid header / library Stefan Weil
2009-07-23 20:29 ` [Qemu-devel] [PATCH] Add new block driver for the VDI format (use aio) Stefan Weil
2009-07-24 9:18 ` Kevin Wolf
2009-07-24 16:20 ` Stefan Weil
2009-07-27 8:00 ` Kevin Wolf
2009-07-27 9:23 ` Jamie Lokier [this message]
2009-07-28 6:37 ` Amit Shah
2009-07-28 8:34 ` Jamie Lokier
2009-07-28 8:56 ` Daniel P. Berrange
2009-07-28 9:03 ` Jamie Lokier
2009-07-28 9:11 ` Kevin Wolf
2009-07-31 15:04 ` Christoph Hellwig
2009-07-31 19:53 ` Stefan Weil
2009-07-31 15:25 ` Anthony Liguori
2009-07-31 18:27 ` Stefan Weil
2009-07-31 19:45 ` [Qemu-devel] [PATCH] Add new block driver for the VDI format (only aio supported) Stefan Weil
2009-07-23 20:30 ` [Qemu-devel] [PATCH] add support for new option of vdi format Stefan Weil
2009-07-23 20:34 ` [Qemu-devel] " Stefan Weil
2009-07-31 14:59 ` [Qemu-devel] " Christoph Hellwig
2009-08-13 16:53 ` Christoph Hellwig
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