Re: [Qemu-devel] [PATCH V2] block/io: optimize bdrv_co_pwritev for small requests

Am 30.05.2016 um 12:06 schrieb Kevin Wolf: Am 30.05.2016 um 11:53 hat Peter Lieven geschrieben: Am 30.05.2016 um 11:47 schrieb Kevin Wolf: Am 30.05.2016 um 11:30 hat Peter Lieven geschrieben: Am 30.05.2016 um 10:24 schrieb Kevin Wolf: Am 30.05.2016 um 08:25 hat Peter Lieven geschrieben: Am 2

Re: [Qemu-devel] [PATCH V2] block/io: optimize bdrv_co_pwritev for small requests

Am 30.05.2016 um 11:53 hat Peter Lieven geschrieben: > Am 30.05.2016 um 11:47 schrieb Kevin Wolf: > >Am 30.05.2016 um 11:30 hat Peter Lieven geschrieben: > >>Am 30.05.2016 um 10:24 schrieb Kevin Wolf: > >>>Am 30.05.2016 um 08:25 hat Peter Lieven geschrieben: > Am 27.05.2016 um 10:55 schrieb Kev

Re: [Qemu-devel] [PATCH V2] block/io: optimize bdrv_co_pwritev for small requests

Am 30.05.2016 um 11:47 schrieb Kevin Wolf: Am 30.05.2016 um 11:30 hat Peter Lieven geschrieben: Am 30.05.2016 um 10:24 schrieb Kevin Wolf: Am 30.05.2016 um 08:25 hat Peter Lieven geschrieben: Am 27.05.2016 um 10:55 schrieb Kevin Wolf: Am 27.05.2016 um 02:36 hat Fam Zheng geschrieben: On Thu,

Re: [Qemu-devel] [PATCH V2] block/io: optimize bdrv_co_pwritev for small requests

Am 30.05.2016 um 11:30 hat Peter Lieven geschrieben: > Am 30.05.2016 um 10:24 schrieb Kevin Wolf: > >Am 30.05.2016 um 08:25 hat Peter Lieven geschrieben: > >>Am 27.05.2016 um 10:55 schrieb Kevin Wolf: > >>>Am 27.05.2016 um 02:36 hat Fam Zheng geschrieben: > On Thu, 05/26 11:20, Paolo Bonzini wr

Re: [Qemu-devel] [PATCH V2] block/io: optimize bdrv_co_pwritev for small requests

Am 30.05.2016 um 10:24 schrieb Kevin Wolf: Am 30.05.2016 um 08:25 hat Peter Lieven geschrieben: Am 27.05.2016 um 10:55 schrieb Kevin Wolf: Am 27.05.2016 um 02:36 hat Fam Zheng geschrieben: On Thu, 05/26 11:20, Paolo Bonzini wrote: On 26/05/2016 10:30, Fam Zheng wrote: This doesn't look too w

Re: [Qemu-devel] [PATCH V2] block/io: optimize bdrv_co_pwritev for small requests

Am 30.05.2016 um 08:25 hat Peter Lieven geschrieben: > Am 27.05.2016 um 10:55 schrieb Kevin Wolf: > >Am 27.05.2016 um 02:36 hat Fam Zheng geschrieben: > >>On Thu, 05/26 11:20, Paolo Bonzini wrote: > >>>On 26/05/2016 10:30, Fam Zheng wrote: > >>This doesn't look too wrong... Should the right se

Re: [Qemu-devel] [PATCH V2] block/io: optimize bdrv_co_pwritev for small requests

Am 27.05.2016 um 10:55 schrieb Kevin Wolf: Am 27.05.2016 um 02:36 hat Fam Zheng geschrieben: On Thu, 05/26 11:20, Paolo Bonzini wrote: On 26/05/2016 10:30, Fam Zheng wrote: This doesn't look too wrong... Should the right sequence of events be head/after_head or head/after_tail? It's probably

Re: [Qemu-devel] [PATCH V2] block/io: optimize bdrv_co_pwritev for small requests

Am 27.05.2016 um 02:36 hat Fam Zheng geschrieben: > On Thu, 05/26 11:20, Paolo Bonzini wrote: > > On 26/05/2016 10:30, Fam Zheng wrote: > > >> > > > >> > This doesn't look too wrong... Should the right sequence of events be > > >> > head/after_head or head/after_tail? It's probably simplest to j

Re: [Qemu-devel] [PATCH V2] block/io: optimize bdrv_co_pwritev for small requests

On Thu, 05/26 11:20, Paolo Bonzini wrote: > > > On 26/05/2016 10:30, Fam Zheng wrote: > >> > > >> > This doesn't look too wrong... Should the right sequence of events be > >> > head/after_head or head/after_tail? It's probably simplest to just emit > >> > all four events. > > I've no idea. (Th

Re: [Qemu-devel] [PATCH V2] block/io: optimize bdrv_co_pwritev for small requests

On 26/05/2016 10:30, Fam Zheng wrote: >> > >> > This doesn't look too wrong... Should the right sequence of events be >> > head/after_head or head/after_tail? It's probably simplest to just emit >> > all four events. > I've no idea. (That's why I leaned towards fixing the test case). Well, fi

Re: [Qemu-devel] [PATCH V2] block/io: optimize bdrv_co_pwritev for small requests

On Thu, 05/26 09:55, Paolo Bonzini wrote: > > > On 26/05/2016 09:10, Fam Zheng wrote: > > > > diff --git a/block/io.c b/block/io.c > > index d480097..a6523cf 100644 > > --- a/block/io.c > > +++ b/block/io.c > > @@ -1435,8 +1435,10 @@ int coroutine_fn bdrv_co_pwritev(BlockDriverState > > *bs, >

Re: [Qemu-devel] [PATCH V2] block/io: optimize bdrv_co_pwritev for small requests

On 26/05/2016 09:10, Fam Zheng wrote: > > diff --git a/block/io.c b/block/io.c > index d480097..a6523cf 100644 > --- a/block/io.c > +++ b/block/io.c > @@ -1435,8 +1435,10 @@ int coroutine_fn bdrv_co_pwritev(BlockDriverState *bs, > * than one aligned block. > */ > if

Re: [Qemu-devel] [PATCH V2] block/io: optimize bdrv_co_pwritev for small requests

On Thu, 05/26 14:50, Fam Zheng wrote: > On Tue, 05/24 16:30, Peter Lieven wrote: > > in a read-modify-write cycle a small request might cause > > head and tail to fall into the same aligned block. Currently > > QEMU reads the same block twice in this case which is > > not necessary. > > > > Signed

Re: [Qemu-devel] [PATCH V2] block/io: optimize bdrv_co_pwritev for small requests

On Tue, 05/24 16:30, Peter Lieven wrote: > in a read-modify-write cycle a small request might cause > head and tail to fall into the same aligned block. Currently > QEMU reads the same block twice in this case which is > not necessary. > > Signed-off-by: Peter Lieven Thanks, applied to my block

Re: [Qemu-devel] [PATCH V2] block/io: optimize bdrv_co_pwritev for small requests

Am 24.05.2016 um 16:30 hat Peter Lieven geschrieben: > in a read-modify-write cycle a small request might cause > head and tail to fall into the same aligned block. Currently > QEMU reads the same block twice in this case which is > not necessary. > > Signed-off-by: Peter Lieven Reviewed-by: Kev

[Qemu-devel] [PATCH V2] block/io: optimize bdrv_co_pwritev for small requests

in a read-modify-write cycle a small request might cause head and tail to fall into the same aligned block. Currently QEMU reads the same block twice in this case which is not necessary. Signed-off-by: Peter Lieven --- v1->v2: following Paolos suggestions to simplify the if condition and