On Wed, Apr 19, 2023 at 1:50 PM Hawkins Jiawei <yin31...@gmail.com> wrote: > > This patchset allows QEMU to poll and check the device used buffer > after sending all SVQ control commands, instead of polling and checking > immediately after sending each SVQ control command, so that QEMU can > send all the SVQ control commands in parallel, which have better > performance improvement. > > I use vdpa_sim_net to simulate vdpa device, refactor > vhost_vdpa_net_load() to call vhost_vdpa_net_load_mac() 30 times, > refactor `net_vhost_vdpa_cvq_info.load` to call vhost_vdpa_net_load() > 1000 times,
Maybe a little bit too high for real scenarios but it gives us a hint for sure :). Maybe it is more realistic to send ~10 or ~100 commands? > to build a test environment for sending > multiple SVQ control commands. Time in monotonic to > finish `net_vhost_vdpa_cvq_info.load`: > > QEMU monotonic time > -------------------------------------------------- > not patched 89202 > -------------------------------------------------- > patched 80455 > Is time expressed in seconds or milliseconds? I'm going to assume ms. So let's say all the time was spent in the context switch between qemu and kernel, this is a save of (89202 - 80455)/30000 = 0.3 ms per command? Thanks! > This patchset resolves the GitLab issue at > https://gitlab.com/qemu-project/qemu/-/issues/1578. > > Hawkins Jiawei (2): > vdpa: rename vhost_vdpa_net_cvq_add() > vdpa: send CVQ state load commands in parallel > > net/vhost-vdpa.c | 150 +++++++++++++++++++++++++++++++++++------------ > 1 file changed, 112 insertions(+), 38 deletions(-) > > -- > 2.25.1 >
