[libvirt] v3: Use posix_fallocate() on supported systems to allocate diskspace

[Daniel P. Berrange]

On Thu, Mar 19, 2009 at 09:47:12PM +0530, Amit Shah wrote:
> On (Thu) Mar 19 2009 [20:17:52], Amit Shah wrote:
> > This patchset makes use of the posix_fallocate() call to allocate
> > chunks of files whenever needed if it's available.
> > 
> > We fallback to using safewrite() if it's not available.
> > 
> > mmap() could be used instead of safewrite too; I have a patch in case
> > someone is interested in seeing it.
> 
> Something like this:
> 
> >From d33b843b381ea6a25c6e8efb6b248965a40e5f84 Mon Sep 17 00:00:00 2001
> From: Amit Shah <amit.shah at redhat.com>
> Date: Thu, 19 Mar 2009 21:43:50 +0530
> Subject: [PATCH] Use mmap() and memset() for safezero
> 
> If available, use mmap to allocate zeroed chunks for files. This
> should be faster than allocating small chunks using safewrite.
> 
> Signed-off-by: Amit Shah <amit.shah at redhat.com>

ACK, looks like a good extension.

Daniel
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