On 2018/06/30 1:38, Michael S. Tsirkin wrote:
...

quoted

Performance numbers:

- Bulk transfer from guest to external physical server.
    [Guest]->vhost_net->tap--(XDP_REDIRECT)-->i40e --(wire)--> [Server]
- Set 10us busypoll.
- Guest disables checksum and TSO because of host XDP.
- Measured single flow Mbps by netperf, and kicks by perf kvm stat
  (EPT_MISCONFIG event).

                            Before              After
                          Mbps  kicks/s      Mbps  kicks/s
UDP_STREAM 1472byte              247758                 27
                Send   3645.37            6958.10
                Recv   3588.56            6958.10
              1byte                9865                 37
                Send      4.34               5.43
                Recv      4.17               5.26
TCP_STREAM             8801.03    45794   9592.77     2884

Signed-off-by: Toshiaki Makita <redacted>

Is this with busy poll enabled?

Yes, as I wrote "Set 10us busypoll" above.

Are there CPU utilization #s?

I used one cpu for one vcpu and one cpu for one vhost.
Each host cpu for vcpu/vhost was like this:

- Before
 vcpu cpu : %guest 70 %sys 30
 vhost cpu: %sys 100

- After
 vcpu cpu : %guest 100
 vhost cpu: %sys 100

I think %sys before patch was caused by vring kick.

-- 
Toshiaki Makita