On Mon, Oct 26, 2015 at 02:53:38PM +0800, Jason Wang wrote: > > > On 10/26/2015 02:09 PM, Michael S. Tsirkin wrote: > > On Mon, Oct 26, 2015 at 11:15:57AM +0800, Jason Wang wrote: > >> > >> On 10/23/2015 09:37 PM, Michael S. Tsirkin wrote: > >>> On Fri, Oct 23, 2015 at 12:57:05AM -0400, Jason Wang wrote: > >>>> We don't have fraglist support in TAP_FEATURES. This will lead > >>>> software segmentation of gro skb with frag list. Fixes by having > >>>> frag list support in TAP_FEATURES. > >>>> > >>>> With this patch single session of netperf receiving were restored from > >>>> about 5Gb/s to about 12Gb/s on mlx4. > >>>> > >>>> Fixes a567dd6252 ("macvtap: simplify usage of tap_features") > >>>> Cc: Vlad Yasevich <vyase...@redhat.com> > >>>> Cc: Michael S. Tsirkin <m...@redhat.com> > >>>> Signed-off-by: Jason Wang <jasow...@redhat.com> > >>> Thanks! > >>> Does this mean we should look at re-adding NETIF_F_FRAGLIST > >>> to virtio-net as well? > >> Not sure I get the point, but probably not. This is for receiving and > >> skb_copy_datagram_iter() can deal with frag list. > > > > Point is: > > - bridge within guest > > - assigned device creating gro skbs with frag list bridged to virtio > > I see, but this problem looks not specific to virtio. Most cards does > not support frag list.
These will be slower when used with a bridge then, won't they? -- MST -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/