similar to: [RFC] 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 > >

> -----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. 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

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

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

> -----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:

Hi Daniel, Other than crosvm, is there any version of qemu (e.g., repositories developed in progress on github) where I can try with this feature? Thank you very much! Dongli Zhang On 11/02/2018 06:40 AM, Daniel Verkamp wrote: > From: Changpeng Liu <changpeng.liu at intel.com> > > In commit 88c85538, "virtio-blk: add discard and write zeroes features > to

On Thu, Nov 01, 2018 at 03:40:35PM -0700, Daniel Verkamp wrote: > From: Changpeng Liu <changpeng.liu at intel.com> > > In commit 88c85538, "virtio-blk: add discard and write zeroes features > to specification" (https://github.com/oasis-tcs/virtio-spec), the virtio > block specification has been extended to add VIRTIO_BLK_T_DISCARD and > VIRTIO_BLK_T_WRITE_ZEROES

> -----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 redhat.com; pbonzini at redhat.com; Wang, Wei W > <wei.w.wang at intel.com> > Subject: Re: [PATCH v6]

> -----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 redhat.com; pbonzini at redhat.com; Wang, Wei W > <wei.w.wang at intel.com> > Subject: Re: [PATCH v6]

> -----Original Message----- > From: Stefan Hajnoczi [mailto:stefanha at redhat.com] > Sent: Friday, June 8, 2018 6:20 PM > To: Liu, Changpeng <changpeng.liu at intel.com> > Cc: virtualization at lists.linux-foundation.org; cavery at redhat.com; > jasowang at redhat.com; pbonzini at redhat.com; Wang, Wei W > <wei.w.wang at intel.com> > Subject: Re: [PATCH v6]

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.

On Fri, Oct 12, 2018 at 02:06:28PM -0700, Daniel Verkamp wrote: > From: Changpeng Liu <changpeng.liu at intel.com> > > In commit 88c85538, "virtio-blk: add discard and write zeroes features > to specification" (https://github.com/oasis-tcs/virtio-spec), the virtio There is some issues in this spec. For one using the multiple ranges also for write zeroes is rather