From: David S. Miller Date: Fri, 17 Jan 2014 07:46:17 +0000 (-0800) Subject: Merge branch 'virtio_rx_merging' X-Git-Url: http://pileus.org/git/?a=commitdiff_plain;h=cf84eb0b09c0f09b4c70a648b9dfeec78be61f07;hp=fbf28d78f54016faa7f0b68cf632ac739f2204f7;p=~andy%2Flinux Merge branch 'virtio_rx_merging' Michael Dalton says: ==================== virtio-net: mergeable rx buffer size auto-tuning The virtio-net device currently uses aligned MTU-sized mergeable receive packet buffers. Network throughput for workloads with large average packet size can be improved by posting larger receive packet buffers. However, due to SKB truesize effects, posting large (e.g, PAGE_SIZE) buffers reduces the throughput of workloads that do not benefit from GRO and have no large inbound packets. This patchset introduces virtio-net mergeable buffer size auto-tuning, with buffer sizes ranging from aligned MTU-size to PAGE_SIZE. Packet buffer size is chosen based on a per-receive queue EWMA of incoming packet size. To unify mergeable receive buffer memory allocation and improve SKB frag coalescing, all mergeable buffer memory allocation is migrated to per-receive queue page frag allocators. The per-receive queue mergeable packet buffer size is exported via sysfs, and the network device sysfs layer has been extended to add support for device-specific per-receive queue sysfs attribute groups. ==================== Signed-off-by: David S. Miller ---