Searched hist:c9b7d9ec (Results 1 – 3 of 3) sorted by relevance
/qemu/hw/scsi/ |
H A D | virtio-scsi.c | c9b7d9ec Fri Feb 14 07:46:48 GMT 2020 Denis Plotnikov <dplotnikov@virtuozzo.com> virtio: increase virtqueue size for virtio-scsi and virtio-blk
The goal is to reduce the amount of requests issued by a guest on 1M reads/writes. This rises the performance up to 4% on that kind of disk access pattern.
The maximum chunk size to be used for the guest disk accessing is limited with seg_max parameter, which represents the max amount of pices in the scatter-geather list in one guest disk request.
Since seg_max is virqueue_size dependent, increasing the virtqueue size increases seg_max, which, in turn, increases the maximum size of data to be read/write from a guest disk.
More details in the original problem statment: https://lists.gnu.org/archive/html/qemu-devel/2017-12/msg03721.html
Suggested-by: Denis V. Lunev <den@openvz.org> Signed-off-by: Denis Plotnikov <dplotnikov@virtuozzo.com> Message-id: 20200214074648.958-1-dplotnikov@virtuozzo.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
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/qemu/hw/block/ |
H A D | virtio-blk.c | c9b7d9ec Fri Feb 14 07:46:48 GMT 2020 Denis Plotnikov <dplotnikov@virtuozzo.com> virtio: increase virtqueue size for virtio-scsi and virtio-blk
The goal is to reduce the amount of requests issued by a guest on 1M reads/writes. This rises the performance up to 4% on that kind of disk access pattern.
The maximum chunk size to be used for the guest disk accessing is limited with seg_max parameter, which represents the max amount of pices in the scatter-geather list in one guest disk request.
Since seg_max is virqueue_size dependent, increasing the virtqueue size increases seg_max, which, in turn, increases the maximum size of data to be read/write from a guest disk.
More details in the original problem statment: https://lists.gnu.org/archive/html/qemu-devel/2017-12/msg03721.html
Suggested-by: Denis V. Lunev <den@openvz.org> Signed-off-by: Denis Plotnikov <dplotnikov@virtuozzo.com> Message-id: 20200214074648.958-1-dplotnikov@virtuozzo.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
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/qemu/hw/core/ |
H A D | machine.c | c9b7d9ec Fri Feb 14 07:46:48 GMT 2020 Denis Plotnikov <dplotnikov@virtuozzo.com> virtio: increase virtqueue size for virtio-scsi and virtio-blk
The goal is to reduce the amount of requests issued by a guest on 1M reads/writes. This rises the performance up to 4% on that kind of disk access pattern.
The maximum chunk size to be used for the guest disk accessing is limited with seg_max parameter, which represents the max amount of pices in the scatter-geather list in one guest disk request.
Since seg_max is virqueue_size dependent, increasing the virtqueue size increases seg_max, which, in turn, increases the maximum size of data to be read/write from a guest disk.
More details in the original problem statment: https://lists.gnu.org/archive/html/qemu-devel/2017-12/msg03721.html
Suggested-by: Denis V. Lunev <den@openvz.org> Signed-off-by: Denis Plotnikov <dplotnikov@virtuozzo.com> Message-id: 20200214074648.958-1-dplotnikov@virtuozzo.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
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