From: Tonghao Zhang <xiangxia.m....@gmail.com> This patch improves the guest receive and transmit performance. On the handle_tx side, we poll the sock receive queue at the same time. handle_rx do that in the same way.
We set the poll-us=100us and use the iperf3 to test its bandwidth, use the netperf to test throughput and mean latency. When running the tests, the vhost-net kthread of that VM, is alway 100% CPU. The commands are shown as below. iperf3 -s -D iperf3 -c IP -i 1 -P 1 -t 20 -M 1400 or netserver netperf -H IP -t TCP_RR -l 20 -- -O "THROUGHPUT,MEAN_LATENCY" host -> guest: iperf3: * With the patch: 27.0 Gbits/sec * Without the patch: 14.4 Gbits/sec netperf (TCP_RR): * With the patch: 48039.56 trans/s, 20.64us mean latency * Without the patch: 46027.07 trans/s, 21.58us mean latency This patch also improves the guest transmit performance. guest -> host: iperf3: * With the patch: 27.2 Gbits/sec * Without the patch: 24.4 Gbits/sec netperf (TCP_RR): * With the patch: 47963.25 trans/s, 20.71us mean latency * Without the patch: 45796.70 trans/s, 21.68us mean latency Signed-off-by: Tonghao Zhang <zhangtong...@didichuxing.com> --- drivers/vhost/net.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-) diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index 458f81d..fb43d82 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -478,17 +478,13 @@ static int vhost_net_tx_get_vq_desc(struct vhost_net *net, struct iovec iov[], unsigned int iov_size, unsigned int *out_num, unsigned int *in_num) { - unsigned long uninitialized_var(endtime); + struct vhost_net_virtqueue *nvq_rx = &net->vqs[VHOST_NET_VQ_RX]; int r = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov), out_num, in_num, NULL, NULL); if (r == vq->num && vq->busyloop_timeout) { - preempt_disable(); - endtime = busy_clock() + vq->busyloop_timeout; - while (vhost_can_busy_poll(vq->dev, endtime) && - vhost_vq_avail_empty(vq->dev, vq)) - cpu_relax(); - preempt_enable(); + vhost_net_busy_poll(net, &nvq_rx->vq, vq, false); + r = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov), out_num, in_num, NULL, NULL); } -- 1.8.3.1 _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization