On Fri, Jun 19, 2020 at 08:07:57PM +0200, Eugenio Perez Martin wrote: > On Mon, Jun 15, 2020 at 2:28 PM Eugenio Perez Martin > <eperezma@xxxxxxxxxx> wrote: > > > > On Thu, Jun 11, 2020 at 5:22 PM Konrad Rzeszutek Wilk > > <konrad.wilk@xxxxxxxxxx> wrote: > > > > > > On Thu, Jun 11, 2020 at 07:34:19AM -0400, Michael S. Tsirkin wrote: > > > > As testing shows no performance change, switch to that now. > > > > > > What kind of testing? 100GiB? Low latency? > > > > > > > Hi Konrad. > > > > I tested this version of the patch: > > https://lkml.org/lkml/2019/10/13/42 > > > > It was tested for throughput with DPDK's testpmd (as described in > > http://doc.dpdk.org/guides/howto/virtio_user_as_exceptional_path.html) > > and kernel pktgen. No latency tests were performed by me. Maybe it is > > interesting to perform a latency test or just a different set of tests > > over a recent version. > > > > Thanks! > > I have repeated the tests with v9, and results are a little bit different: > * If I test opening it with testpmd, I see no change between versions OK that is testpmd on guest, right? And vhost-net on the host? > * If I forward packets between two vhost-net interfaces in the guest > using a linux bridge in the host: And here I guess you mean virtio-net in the guest kernel? > - netperf UDP_STREAM shows a performance increase of 1.8, almost > doubling performance. This gets lower as frame size increase. > - rests of the test goes noticeably worse: UDP_RR goes from ~6347 > transactions/sec to 5830 OK so it seems plausible that we still have a bug where an interrupt is delayed. That is the main difference between pmd and virtio. Let's try disabling event index, and see what happens - that's the trickiest part of interrupts. > - TCP_STREAM goes from ~10.7 gbps to ~7Gbps > - TCP_RR from 6223.64 transactions/sec to 5739.44
