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Re: [Xen-devel] [PATCH][RFC] open HVM backing storage with O_SYNC

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Subject: Re: [Xen-devel] [PATCH][RFC] open HVM backing storage with O_SYNC
From: Rik van Riel <riel@xxxxxxxxxx>
Date: Fri, 28 Jul 2006 13:02:40 -0400
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Rik van Riel wrote:

Any comments on this patch?

I got some comments from Alan, who would like to see this behaviour
tunable with hdparm from inside the guest.  This requires larger
qemu changes though, to be specific an ->fsync callback into each
of the backing store drivers, so that is something for the qemu
mailing list.

The current bottleneck seems to be that MAX_MULT_COUNT is only 16.
I will try raising this to 256 so we can transport a lot more data
per world and domain switch...

"Debugging is twice as hard as writing the code in the first place.
Therefore, if you write the code as cleverly as possible, you are,
by definition, not smart enough to debug it." - Brian W. Kernighan

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