[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Qemu-devel] [PATCH] Align file accesses with cache=off (O_DIRECT)

From: Kevin Wolf
Subject: Re: [Qemu-devel] [PATCH] Align file accesses with cache=off (O_DIRECT)
Date: Mon, 28 Apr 2008 17:34:33 +0200
User-agent: Thunderbird (X11/20060911)

Kevin Wolf schrieb:
> In December a patch was applied which introduced the cache=off option to
> -drive. When using this option files are opened with the O_DIRECT flag.
> This means that all accesses have to be aligned. The patch made a couple
> of changes in this respect, still in other places they are missing (e.g.
> you can't use cache=off with qcow(2) files).
> This patch implements wrappers for raw_pread and raw_pwrite which align
> all file accesses and make qcow(2) work with cache=off. This method
> might not be the most performant one (compared to fixing qcow, qcow2 and
> everything else that might be using unaligned accesses), but unaligned
> accesses don't happen that frequently and with this patch really all
> image accesses should be covered.
> Signed-off-by: Kevin Wolf <address@hidden>

Anything wrong with this one?


reply via email to

[Prev in Thread] Current Thread [Next in Thread]