Re: [PATCH 1/1] virtio-blk-ccw: tweak the default for num_queues

2020-12-15 Thread Cornelia Huck
On Tue, 15 Dec 2020 12:33:34 +0100 Halil Pasic wrote: > On Tue, 15 Dec 2020 09:26:56 +0100 > Cornelia Huck wrote: > > Do we have a better idea now about which values would make sense here? > > > > Hi Conny! > > I have nothing new since then. Capping at 4 queues still looks like a >

Re: [PATCH 1/1] virtio-blk-ccw: tweak the default for num_queues

2020-12-15 Thread Halil Pasic
On Tue, 15 Dec 2020 09:26:56 +0100 Cornelia Huck wrote: > On Tue, 10 Nov 2020 14:18:39 +0100 > Christian Borntraeger wrote: > > > On 10.11.20 11:40, Halil Pasic wrote: > > > On Tue, 10 Nov 2020 09:47:51 +0100 > > > Christian Borntraeger wrote: > > > > > >> > > >> > > >> On 09.11.20 19:53,

Re: [PATCH 1/1] virtio-blk-ccw: tweak the default for num_queues

2020-12-15 Thread Cornelia Huck
On Tue, 10 Nov 2020 14:18:39 +0100 Christian Borntraeger wrote: > On 10.11.20 11:40, Halil Pasic wrote: > > On Tue, 10 Nov 2020 09:47:51 +0100 > > Christian Borntraeger wrote: > > > >> > >> > >> On 09.11.20 19:53, Halil Pasic wrote: > >>> On Mon, 9 Nov 2020 17:06:16 +0100 > >>> Cornelia

Re: [PATCH 1/1] virtio-blk-ccw: tweak the default for num_queues

2020-11-12 Thread Halil Pasic
On Wed, 11 Nov 2020 13:49:08 +0100 Michael Mueller wrote: > Halil, > > still I would like to know what the exact memory consumption per queue > is that you are talking about. Have you made a calculation? Thanks. Hi! The default size for virtio-blk seems to be 256 ring entries, which

Re: [PATCH 1/1] virtio-blk-ccw: tweak the default for num_queues

2020-11-11 Thread Michael Mueller
On 11.11.20 13:38, Cornelia Huck wrote: On Wed, 11 Nov 2020 13:26:11 +0100 Michael Mueller wrote: On 10.11.20 15:16, Michael Mueller wrote: On 09.11.20 19:53, Halil Pasic wrote: On Mon, 9 Nov 2020 17:06:16 +0100 Cornelia Huck wrote: @@ -20,6 +21,11 @@ static void

Re: [PATCH 1/1] virtio-blk-ccw: tweak the default for num_queues

2020-11-11 Thread Cornelia Huck
On Wed, 11 Nov 2020 13:26:11 +0100 Michael Mueller wrote: > On 10.11.20 15:16, Michael Mueller wrote: > > > > > > On 09.11.20 19:53, Halil Pasic wrote: > >> On Mon, 9 Nov 2020 17:06:16 +0100 > >> Cornelia Huck wrote: > >> > @@ -20,6 +21,11 @@ static void >

Re: [PATCH 1/1] virtio-blk-ccw: tweak the default for num_queues

2020-11-11 Thread Michael Mueller
On 10.11.20 15:16, Michael Mueller wrote: On 09.11.20 19:53, Halil Pasic wrote: On Mon, 9 Nov 2020 17:06:16 +0100 Cornelia Huck wrote: @@ -20,6 +21,11 @@ static void virtio_ccw_blk_realize(VirtioCcwDevice *ccw_dev, Error **errp)   {   VirtIOBlkCcw *dev = VIRTIO_BLK_CCW(ccw_dev);    

Re: [PATCH 1/1] virtio-blk-ccw: tweak the default for num_queues

2020-11-10 Thread Michael Mueller
On 09.11.20 19:53, Halil Pasic wrote: On Mon, 9 Nov 2020 17:06:16 +0100 Cornelia Huck wrote: @@ -20,6 +21,11 @@ static void virtio_ccw_blk_realize(VirtioCcwDevice *ccw_dev, Error **errp) { VirtIOBlkCcw *dev = VIRTIO_BLK_CCW(ccw_dev); DeviceState *vdev = DEVICE(>vdev); +

Re: [PATCH 1/1] virtio-blk-ccw: tweak the default for num_queues

2020-11-10 Thread Christian Borntraeger
On 10.11.20 11:40, Halil Pasic wrote: > On Tue, 10 Nov 2020 09:47:51 +0100 > Christian Borntraeger wrote: > >> >> >> On 09.11.20 19:53, Halil Pasic wrote: >>> On Mon, 9 Nov 2020 17:06:16 +0100 >>> Cornelia Huck wrote: >>> > @@ -20,6 +21,11 @@ static void

Re: [PATCH 1/1] virtio-blk-ccw: tweak the default for num_queues

2020-11-10 Thread Halil Pasic
On Tue, 10 Nov 2020 09:47:51 +0100 Christian Borntraeger wrote: > > > On 09.11.20 19:53, Halil Pasic wrote: > > On Mon, 9 Nov 2020 17:06:16 +0100 > > Cornelia Huck wrote: > > > >>> @@ -20,6 +21,11 @@ static void virtio_ccw_blk_realize(VirtioCcwDevice > >>> *ccw_dev, Error **errp) > >>> { >

Re: [PATCH 1/1] virtio-blk-ccw: tweak the default for num_queues

2020-11-10 Thread Cornelia Huck
On Tue, 10 Nov 2020 09:47:51 +0100 Christian Borntraeger wrote: > On 09.11.20 19:53, Halil Pasic wrote: > > On Mon, 9 Nov 2020 17:06:16 +0100 > > Cornelia Huck wrote: > > > >>> @@ -20,6 +21,11 @@ static void virtio_ccw_blk_realize(VirtioCcwDevice > >>> *ccw_dev, Error **errp) > >>> { > >>>

Re: [PATCH 1/1] virtio-blk-ccw: tweak the default for num_queues

2020-11-10 Thread Christian Borntraeger
On 09.11.20 19:53, Halil Pasic wrote: > On Mon, 9 Nov 2020 17:06:16 +0100 > Cornelia Huck wrote: > >>> @@ -20,6 +21,11 @@ static void virtio_ccw_blk_realize(VirtioCcwDevice >>> *ccw_dev, Error **errp) >>> { >>> VirtIOBlkCcw *dev = VIRTIO_BLK_CCW(ccw_dev); >>> DeviceState *vdev =

Re: [PATCH 1/1] virtio-blk-ccw: tweak the default for num_queues

2020-11-09 Thread Halil Pasic
On Mon, 9 Nov 2020 17:06:16 +0100 Cornelia Huck wrote: > > @@ -20,6 +21,11 @@ static void virtio_ccw_blk_realize(VirtioCcwDevice > > *ccw_dev, Error **errp) > > { > > VirtIOBlkCcw *dev = VIRTIO_BLK_CCW(ccw_dev); > > DeviceState *vdev = DEVICE(>vdev); > > +VirtIOBlkConf *conf =

Re: [PATCH 1/1] virtio-blk-ccw: tweak the default for num_queues

2020-11-09 Thread Cornelia Huck
On Mon, 9 Nov 2020 16:48:31 +0100 Halil Pasic wrote: > Currently the default value of num_queues is effectively 1 for > virtio-blk-ccw. Recently 9445e1e15e ("virtio-blk-pci: default num_queues > to -smp N") changed the default for pci to the number of vcpus, citing > interrupt better locality

Re: [PATCH 1/1] virtio-blk-ccw: tweak the default for num_queues

2020-11-09 Thread Christian Borntraeger
On 09.11.20 16:48, Halil Pasic wrote: > Currently the default value of num_queues is effectively 1 for > virtio-blk-ccw. Recently 9445e1e15e ("virtio-blk-pci: default num_queues > to -smp N") changed the default for pci to the number of vcpus, citing > interrupt better locality and better

[PATCH 1/1] virtio-blk-ccw: tweak the default for num_queues

2020-11-09 Thread Halil Pasic
Currently the default value of num_queues is effectively 1 for virtio-blk-ccw. Recently 9445e1e15e ("virtio-blk-pci: default num_queues to -smp N") changed the default for pci to the number of vcpus, citing interrupt better locality and better performance as a rationale. While virtio-blk-ccw does