similar to: [PATCH v2 0/2] virtio_scsi: Set can_queue based on size of virtqueue.

Since switching to blk-mq as the default in commit 5c279bd9e406 ("scsi: default to scsi-mq"), virtio-scsi LUNs consume about 10x as much kernel memory. qemu currently allocates a fixed 128 entry virtqueue. can_queue currently is set to 1024. But with indirect descriptors, each command in the queue takes 1 virtqueue entry, so the number of commands which can be queued is equal to the

This series implements virtio-scsi queue steering, which gives performance improvements of up to 50% (measured both with QEMU and tcm_vhost backends). This version rebased on Rusty's virtio ring rework patches, which has already gone into virtio-next today. We hope this can go into virtio-next together with the virtio ring rework pathes. V6: rework "redo allocation of target data"

This series implements virtio-scsi queue steering, which gives performance improvements of up to 50% (measured both with QEMU and tcm_vhost backends). This version rebased on Rusty's virtio ring rework patches, which has already gone into virtio-next today. We hope this can go into virtio-next together with the virtio ring rework pathes. V6: rework "redo allocation of target data"

This series implements virtio-scsi queue steering, which gives performance improvements of up to 50% (measured both with QEMU and tcm_vhost backends). This version rebased on Rusty's virtio ring rework patches, which has already gone into virtio-next today. We hope this can go into virtio-next together with the virtio ring rework pathes. V7: respin to fix the patch apply error V6: rework

This series implements virtio-scsi queue steering, which gives performance improvements of up to 50% (measured both with QEMU and tcm_vhost backends). This version rebased on Rusty's virtio ring rework patches, which has already gone into virtio-next today. We hope this can go into virtio-next together with the virtio ring rework pathes. V7: respin to fix the patch apply error V6: rework

Earlier discussion: https://lkml.org/lkml/2017/8/4/601 "Increased memory usage with scsi-mq" Downstream bug report: https://bugzilla.redhat.com/show_bug.cgi?id=1478201

Earlier discussion: https://lkml.org/lkml/2017/8/4/601 "Increased memory usage with scsi-mq" Downstream bug report: https://bugzilla.redhat.com/show_bug.cgi?id=1478201

This series implements virtio-scsi queue steering, which gives performance improvements of up to 50% (measured both with QEMU and tcm_vhost backends). This version rebased on Rusty's virtio ring rework patches. We hope this can go into virtio-next together with the virtio ring rework pathes. V5: improving the grammar of 1/5 (Paolo) move the dropping of sg_elems to 'virtio-scsi: use

This series implements virtio-scsi queue steering, which gives performance improvements of up to 50% (measured both with QEMU and tcm_vhost backends). This version rebased on Rusty's virtio ring rework patches. We hope this can go into virtio-next together with the virtio ring rework pathes. V5: improving the grammar of 1/5 (Paolo) move the dropping of sg_elems to 'virtio-scsi: use

Since switching to blk-mq as the default in commit 5c279bd9e406 ("scsi: default to scsi-mq"), virtio-scsi LUNs consume about 10x as much kernel memory. qemu currently allocates a fixed 128 entry virtqueue. can_queue currently is set to 1024. But with indirect descriptors, each command in the queue takes 1 virtqueue entry, so the number of commands which can be queued is equal to the

This series implements virtio-scsi queue steering, which gives performance improvements of up to 50% (measured both with QEMU and tcm_vhost backends). The patches build on top of the new virtio APIs at http://permalink.gmane.org/gmane.linux.kernel.virtualization/18431; the new API simplifies the locking of the virtio-scsi driver nicely, thus it makes sense to require them as a prerequisite.

This series implements virtio-scsi queue steering, which gives performance improvements of up to 50% (measured both with QEMU and tcm_vhost backends). The patches build on top of the new virtio APIs at http://permalink.gmane.org/gmane.linux.kernel.virtualization/18431; the new API simplifies the locking of the virtio-scsi driver nicely, thus it makes sense to require them as a prerequisite.

On Wed, Mar 11, 2020 at 12:25:27AM +0800, John Garry wrote: > From: Hannes Reinecke <hare at suse.com> > > Add a new field 'nr_reserved_cmds' to the SCSI host template to > instruct the block layer to set aside a tag space for reserved > commands. > > Signed-off-by: Hannes Reinecke <hare at suse.com> > --- > drivers/scsi/scsi_lib.c | 1 + >

On Wed, Mar 11, 2020 at 12:25:27AM +0800, John Garry wrote: > From: Hannes Reinecke <hare at suse.com> > > Add a new field 'nr_reserved_cmds' to the SCSI host template to > instruct the block layer to set aside a tag space for reserved > commands. > > Signed-off-by: Hannes Reinecke <hare at suse.com> > --- > drivers/scsi/scsi_lib.c | 1 + >

This series implements virtio-scsi queue steering, which gives performance improvements of up to 50% (measured both with QEMU and tcm_vhost backends). This version rebased on Rusty's virtio ring rework patches. We hope this can go into virtio-next together with the virtio ring rework pathes. V4: rebase on virtio ring rework patches (rusty's pending-rebases branch) V3 and be found

This series implements virtio-scsi queue steering, which gives performance improvements of up to 50% (measured both with QEMU and tcm_vhost backends). This version rebased on Rusty's virtio ring rework patches. We hope this can go into virtio-next together with the virtio ring rework pathes. V4: rebase on virtio ring rework patches (rusty's pending-rebases branch) V3 and be found

Hi Michael, hi Jason, This patches applies a few cleanups to the virtio PCI interrupt handling code, and then converts the virtio PCI code to use the automatic MSI-X vectors spreading, as well as using the information in virtio-blk and virtio-scsi to automatically align the blk-mq queues to the MSI-X vectors. Changes since V2: - remove a redundant callback check - calculate ->msix_vectors

Hi Michael, hi Jason, This patches applies a few cleanups to the virtio PCI interrupt handling code, and then converts the virtio PCI code to use the automatic MSI-X vectors spreading, as well as using the information in virtio-blk and virtio-scsi to automatically align the blk-mq queues to the MSI-X vectors. Changes since V2: - remove a redundant callback check - calculate ->msix_vectors

Hi Michael, hi Jason, This patches applies a few cleanups to the virtio PCI interrupt handling code, and then converts the virtio PCI code to use the automatic MSI-X vectors spreading, as well as using the information in virtio-blk and virtio-scsi to automatically align the blk-mq queues to the MSI-X vectors. Changes since V1: - dropped the patches already merged for 4.10-rc - new patch to

Hi Michael, hi Jason, This patches applies a few cleanups to the virtio PCI interrupt handling code, and then converts the virtio PCI code to use the automatic MSI-X vectors spreading, as well as using the information in virtio-blk and virtio-scsi to automatically align the blk-mq queues to the MSI-X vectors. Changes since V1: - dropped the patches already merged for 4.10-rc - new patch to