similar to: [RFC] virtio_blk: add DISCARD support to virtio_blk driver

Currently virtio_blk driver does not provide discard feature flag, so the filesystems which built on top of the block device will not send discard command. This is okay for HDD backend, but it will impact the performance for SSD backend. Add a feature flag such as VIRTIO_BLK_F_DISCARD to virtio_blk driver is very straightforward, but it will extend the exist virtio_blk protocol, I'm preparing

Currently virtio_blk driver does not provide discard feature flag, so the filesystems which built on top of the block device will not send discard command. This is okay for HDD backend, but it will impact the performance for SSD backend. Add a feature flag such as VIRTIO_BLK_F_DISCARD to virtio_blk driver is very straightforward, but it will extend the exist virtio_blk protocol, I'm preparing

> -----Original Message----- > From: Paolo Bonzini [mailto:pbonzini at redhat.com] > Sent: Tuesday, July 4, 2017 5:24 PM > To: Liu, Changpeng <changpeng.liu at intel.com>; virtualization at lists.linux- > foundation.org > Cc: stefanha at gmail.com; hch at lst.de; mst at redhat.com > Subject: Re: [PATCH v2] virtio-blk: add DISCARD support to virtio-blk driver > >

> -----Original Message----- > From: Paolo Bonzini [mailto:pbonzini at redhat.com] > Sent: Tuesday, July 4, 2017 5:24 PM > To: Liu, Changpeng <changpeng.liu at intel.com>; virtualization at lists.linux- > foundation.org > Cc: stefanha at gmail.com; hch at lst.de; mst at redhat.com > Subject: Re: [PATCH v2] virtio-blk: add DISCARD support to virtio-blk driver > >

Currently virtio-blk driver does not provide discard feature flag, so the filesystems which built on top of the block device will not send discard command. This is okay for HDD backend, but it will impact the performance for SSD backend. Add a feature flag VIRTIO_BLK_F_DISCARD and command VIRTIO_BLK_T_DISCARD to extend exist virtio-blk protocol, define 16 bytes discard descriptor for each discard

Currently virtio-blk driver does not provide discard feature flag, so the filesystems which built on top of the block device will not send discard command. This is okay for HDD backend, but it will impact the performance for SSD backend. Add a feature flag VIRTIO_BLK_F_DISCARD and command VIRTIO_BLK_T_DISCARD to extend exist virtio-blk protocol, define 16 bytes discard descriptor for each discard

On 05/07/2017 10:44, Changpeng Liu wrote: > Currently virtio-blk driver does not provide discard feature flag, so the > filesystems which built on top of the block device will not send discard > command. This is okay for HDD backend, but it will impact the performance > for SSD backend. > > Add a feature flag VIRTIO_BLK_F_DISCARD and command VIRTIO_BLK_T_DISCARD > to extend

On Tue, Mar 28, 2017 at 04:39:25PM +0800, Changpeng Liu wrote: > Currently virtio-blk driver does not provide discard feature flag, so the > filesystems which built on top of the block device will not send discard > command. This is okay for HDD backend, but it will impact the performance > for SSD backend. > > Add a feature flag VIRTIO_BLK_F_DISCARD and command

> -----Original Message----- > From: Stefan Hajnoczi [mailto:stefanha at gmail.com] > Sent: Tuesday, March 28, 2017 4:20 AM > To: Liu, Changpeng <changpeng.liu at intel.com> > Cc: virtio-dev at lists.oasis-open.org; virtualization at lists.linux-foundation.org; linux- > kernel at vger.kernel.org; hch at lst.de; qemu-devel at nongnu.org > Subject: Re: [PATCH] virtio-blk:

> -----Original Message----- > From: Stefan Hajnoczi [mailto:stefanha at gmail.com] > Sent: Tuesday, March 28, 2017 4:20 AM > To: Liu, Changpeng <changpeng.liu at intel.com> > Cc: virtio-dev at lists.oasis-open.org; virtualization at lists.linux-foundation.org; linux- > kernel at vger.kernel.org; hch at lst.de; qemu-devel at nongnu.org > Subject: Re: [PATCH] virtio-blk:

Currently virtio-blk driver does not provide discard feature flag, so the filesystems which built on top of the block device will not send discard command. This is okay for HDD backend, but it will impact the performance for SSD backend. Add a feature flag VIRTIO_BLK_F_DISCARD and command VIRTIO_BLK_T_DISCARD to extend exist virtio-blk protocol. virtio-blk protocol uses a single 8 bytes

Currently virtio-blk driver does not provide discard feature flag, so the filesystems which built on top of the block device will not send discard command. This is okay for HDD backend, but it will impact the performance for SSD backend. Add a feature flag VIRTIO_BLK_F_DISCARD and command VIRTIO_BLK_T_DISCARD to extend exist virtio-blk protocol. virtio-blk protocol uses a single 8 bytes

On Fri, Mar 30, 2018 at 08:49:34AM +0800, Changpeng Liu wrote: > Existing virtio-blk protocol doesn't have DISCARD/WRITE ZEROES > command support, this will impact the performance when using SSD > backend over file systems. > > The idea here is using 16 Bytes payload as one descriptor for > DISCARD/WRITE ZEROES command, users can put several ranges into > one command, for

Existing virtio-blk protocol doesn't have DISCARD/WRITE ZEROES commands support, this will impact the performance when using SSD backend over file systems. Commit 88c85538 "virtio-blk: add discard and write zeroes features to specification"(see https://github.com/oasis-tcs/virtio-spec) extended existing virtio-blk protocol, adding extra DISCARD and WRITE ZEROES commands support.

Existing virtio-blk protocol doesn't have DISCARD/WRITE ZEROES commands support, this will impact the performance when using SSD backend over file systems. Commit 88c85538 "virtio-blk: add discard and write zeroes features to specification"(see https://github.com/oasis-tcs/virtio-spec) extended existing virtio-blk protocol, adding extra DISCARD and WRITE ZEROES commands support.

Existing virtio-blk protocol doesn't have DISCARD/WRITE ZEROES commands support, this will impact the performance when using SSD backend over file systems. Commit 88c85538 "virtio-blk: add discard and write zeroes features to specification"(see https://github.com/oasis-tcs/virtio-spec) extended existing virtio-blk protocol, adding extra DISCARD and WRITE ZEROES commands support.

Existing virtio-blk protocol doesn't have DISCARD/WRITE ZEROES commands support, this will impact the performance when using SSD backend over file systems. Commit 88c85538 "virtio-blk: add discard and write zeroes features to specification"(see https://github.com/oasis-tcs/virtio-spec) extended existing virtio-blk protocol, adding extra DISCARD and WRITE ZEROES commands support.

Existing virtio-blk protocol doesn't have DISCARD/WRITE ZEROES command support, this will impact the performance when using SSD backend over file systems. The idea here is using 16 Bytes payload as one descriptor for DISCARD/WRITE ZEROES command, users can put several ranges into one command, for the purpose to support such feature, two feature flags

Existing virtio-blk protocol doesn't have DISCARD/WRITE ZEROES command support, this will impact the performance when using SSD backend over file systems. The idea here is using 16 Bytes payload as one descriptor for DISCARD/WRITE ZEROES command, users can put several ranges into one command, for the purpose to support such feature, two feature flags

On Thu, Jun 07, 2018 at 11:07:06PM +0000, Liu, Changpeng wrote: > > > > -----Original Message----- > > From: Stefan Hajnoczi [mailto:stefanha at redhat.com] > > Sent: Thursday, June 7, 2018 9:10 PM > > To: Liu, Changpeng <changpeng.liu at intel.com> > > Cc: virtualization at lists.linux-foundation.org; cavery at redhat.com; > > jasowang at