On Fri, Jul 28 2006, Rik van Riel wrote:
> Anthony Liguori wrote:
>
> >Right now Fabrice is working on rewriting the block API to be
> >asynchronous. There's been quite a lot of discussion about why using
> >threads isn't a good idea for this
>
> Agreed, AIO is the way to go in the long run.
>
> > Have you measured the impact of O_SYNC? I wouldn't be surprised if it was
> > significant.
>
> I suspect it'll be horrific in the qemu codebase (blocking execution
> of the guest OS until disk IO is complete), but it's fine in the Xen
> qemu-dm situation, where IO completion happens asynchronou
Paul Brook wrote:
With a proper async API, is there any reason why we would want this to be
tunable? I don't think there's much of a benefit of prematurely claiming
a write is complete especially once the SCSI emulation can support
multiple simultaneous requests.
You're right. This O_SYNC band
> > With a proper async API, is there any reason why we would want this to be
> > tunable? I don't think there's much of a benefit of prematurely claiming
> > a write is complete especially once the SCSI emulation can support
> > multiple simultaneous requests.
>
> You're right. This O_SYNC banda
Anthony Liguori wrote:
Right now Fabrice is working on rewriting the block API to be
asynchronous. There's been quite a lot of discussion about why using
threads isn't a good idea for this
Agreed, AIO is the way to go in the long run.
With a proper async API, is there any reason why we woul
On Fri, 28 Jul 2006 15:54:30 -0400, Rik van Riel wrote:
> This is the simple approach to making sure that disk writes actually hit
> disk before we tell the guest OS that IO has completed. Thanks to
> DMA_MULTI_THREAD the performance still seems to be adequate.
Hi Rik,
Right now Fabrice is work
Rik van Riel wrote:
This is the simple approach to making sure that disk writes actually
hit disk before we tell the guest OS that IO has completed. Thanks
to DMA_MULTI_THREAD the performance still seems to be adequate.
Hah, and of course that bit is only found in Xen's qemu-dm. Doh!
I knew I
