similar to: [PATCH] virtio_balloon: don't call virtio_has_feature() twice on init_vqs()

Leandro Dorileo <l at dorileo.org> writes: > Cchange init_vqs() to avoid calling twice the virtio_has_feature() > - attempting to find out if VIRTIO_BALLOON_F_STATS_VQ feature was negotiated - > consequently we prevent unnecessarily running the drivers' feature_table more > than needed. > > Signed-off-by: Leandro Dorileo <l at dorileo.org> Hi Leandro,

On Wed, Jan 17, 2018 at 01:10:11PM +0800, Wei Wang wrote: > Negotiation of the VIRTIO_BALLOON_F_FREE_PAGE_VQ feature indicates the > support of reporting hints of guest free pages to host via virtio-balloon. > > Host requests the guest to report free pages by sending a new cmd > id to the guest via the free_page_report_cmd_id configuration register. > > When the guest starts

On Wed, Jan 17, 2018 at 01:10:11PM +0800, Wei Wang wrote: > Negotiation of the VIRTIO_BALLOON_F_FREE_PAGE_VQ feature indicates the > support of reporting hints of guest free pages to host via virtio-balloon. > > Host requests the guest to report free pages by sending a new cmd > id to the guest via the free_page_report_cmd_id configuration register. > > When the guest starts

After 86a559787e6f ("virtio-balloon: VIRTIO_BALLOON_F_FREE_PAGE_HINT"), the virtio-balloon device unconditionally specifies 4 virtqueues as the argument to find_vqs(), which means that 5 MSI-X vectors are required in order to assign one vector per VQ plus one for configuration changes. However, in cases where the virtio device only provides exactly as many MSI-X vectors as required for

After 86a559787e6f ("virtio-balloon: VIRTIO_BALLOON_F_FREE_PAGE_HINT"), the virtio-balloon device unconditionally specifies 4 virtqueues as the argument to find_vqs(), which means that 5 MSI-X vectors are required in order to assign one vector per VQ plus one for configuration changes. However, in cases where the virtio device only provides exactly as many MSI-X vectors as required for

The current QEMU live migration implementation mark the all the guest's RAM pages as dirtied in the ram bulk stage, all these pages will be processed and that takes quit a lot of CPU cycles. >From guest's point of view, it doesn't care about the content in free pages. We can make use of this fact and skip processing the free pages in the ram bulk stage, it can save a lot CPU cycles

The current QEMU live migration implementation mark the all the guest's RAM pages as dirtied in the ram bulk stage, all these pages will be processed and that takes quit a lot of CPU cycles. >From guest's point of view, it doesn't care about the content in free pages. We can make use of this fact and skip processing the free pages in the ram bulk stage, it can save a lot CPU cycles

> > Negotiation of the VIRTIO_BALLOON_F_FREE_PAGE_VQ feature indicates the > support of reporting hints of guest free pages to host via virtio-balloon. > > Host requests the guest to report free pages by sending a new cmd > id to the guest via the free_page_report_cmd_id configuration register. > > When the guest starts to report, the first element added to the free page

> > Negotiation of the VIRTIO_BALLOON_F_FREE_PAGE_VQ feature indicates the > support of reporting hints of guest free pages to host via virtio-balloon. > > Host requests the guest to report free pages by sending a new cmd > id to the guest via the free_page_report_cmd_id configuration register. > > When the guest starts to report, the first element added to the free page

Ping for comments, thanks. On 11/03/2017 04:13 PM, Wei Wang wrote: > Negotiation of the VIRTIO_BALLOON_F_FREE_PAGE_VQ feature indicates the > support of reporting hints of guest free pages to the host via > virtio-balloon. The host requests the guest to report the free pages by > sending commands via the virtio-balloon configuration registers. > > When the guest starts to

Ping for comments, thanks. On 11/03/2017 04:13 PM, Wei Wang wrote: > Negotiation of the VIRTIO_BALLOON_F_FREE_PAGE_VQ feature indicates the > support of reporting hints of guest free pages to the host via > virtio-balloon. The host requests the guest to report the free pages by > sending commands via the virtio-balloon configuration registers. > > When the guest starts to

This patch series implements two optimizations: 1) transfer pages in chuncks between the guest and host; 2) transfer the guest unused pages to the host so that they can be skipped to migrate in live migration. Please read each patch commit log for details. Changes: v7->v8: 1) Use only one chunk format, instead of two. 2) re-write the virtio-balloon implementation patch. 3) commit changes 4)

This patch series implements two optimizations: 1) transfer pages in chuncks between the guest and host; 2) transfer the guest unused pages to the host so that they can be skipped to migrate in live migration. Please read each patch commit log for details. Changes: v7->v8: 1) Use only one chunk format, instead of two. 2) re-write the virtio-balloon implementation patch. 3) commit changes 4)

On Mon, Aug 21, 2023 at 03:18:50PM -0700, Daniel Verkamp wrote: > Hello virtio folks, Hi Daniel, I have CCed those involved in the free page hint and page reporting features. Stefan > > I noticed a mismatch between the way the specification defines > device-specific virtqueue indexes and the way device and driver > implementers have interpreted the specification. As a practical

This patch series implements two optimizations: 1) transfer pages in chuncks between the guest and host; 2) transfer the guest unused pages to the host so that they can be skipped to migrate in live migration. Changes: v8->v9: 1) Split the two new features, VIRTIO_BALLOON_F_BALLOON_CHUNKS and VIRTIO_BALLOON_F_MISC_VQ, which were mixed together in the previous implementation; 2) Simpler

This patch series implements two optimizations: 1) transfer pages in chuncks between the guest and host; 2) transfer the guest unused pages to the host so that they can be skipped to migrate in live migration. Changes: v8->v9: 1) Split the two new features, VIRTIO_BALLOON_F_BALLOON_CHUNKS and VIRTIO_BALLOON_F_MISC_VQ, which were mixed together in the previous implementation; 2) Simpler

This patch series is separated from the previous "Virtio-balloon Enhancement" series. The new feature, VIRTIO_BALLOON_F_FREE_PAGE_VQ, implemented by this series enables the virtio-balloon driver to report hints of guest free pages to the host. It can be used to accelerate live migration of VMs. Here is an introduction of this usage: Live migration needs to transfer the VM's memory

This patch series is separated from the previous "Virtio-balloon Enhancement" series. The new feature, VIRTIO_BALLOON_F_FREE_PAGE_VQ, implemented by this series enables the virtio-balloon driver to report hints of guest free pages to the host. It can be used to accelerate live migration of VMs. Here is an introduction of this usage: Live migration needs to transfer the VM's memory

This patch series is separated from the previous "Virtio-balloon Enhancement" series. The new feature, VIRTIO_BALLOON_F_FREE_PAGE_VQ, implemented by this series enables the virtio-balloon driver to report hints of guest free pages to the host. It can be used to accelerate live migration of VMs. Here is an introduction of this usage: Live migration needs to transfer the VM's memory

On 27.08.2018 03:32, Wei Wang wrote: > static int init_vqs(struct virtio_balloon *vb) > { > - struct virtqueue *vqs[3]; > - vq_callback_t *callbacks[] = { balloon_ack, balloon_ack, stats_request }; > - static const char * const names[] = { "inflate", "deflate", "stats" }; > - int err, nvqs; > + struct virtqueue *vqs[VIRTIO_BALLOON_VQ_MAX]; >