diff options
| author |   Jason Wang <jasowang@redhat.com> | 2011-06-10 00:56:17 +0000 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2011-06-11 15:57:47 -0700 |
| commit | 10a8d94a95742bb15b4e617ee9884bb4381362be (patch) | |
| tree | 768f2d92be0e12bca791bcb901ad4bdedc7d8a76 /tools/perf/scripts/python | |
| parent | net: DM9000: Add support for byte EEPROM access (diff) | |
virtio_net: introduce VIRTIO_NET_HDR_F_DATA_VALID
There's no need for the guest to validate the checksum if it have been
validated by host nics. So this patch introduces a new flag -
VIRTIO_NET_HDR_F_DATA_VALID which is used to bypass the checksum
examing in guest. The backend (tap/macvtap) may set this flag when
met skbs with CHECKSUM_UNNECESSARY to save cpu utilization.
No feature negotiation is needed as old driver just ignore this flag.
Iperf shows 12%-30% performance improvement for UDP traffic. For TCP,
when gro is on no difference as it produces skb with partial
checksum. But when gro is disabled, 20% or even higher improvement
could be measured by netperf.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'tools/perf/scripts/python')
0 files changed, 0 insertions, 0 deletions