On Sat, May 6, 2017 at 1:42 PM, Paolo Abeni <pab...@redhat.com> wrote: > This patch series implement an idea suggested by Eric Dumazet to > reduce the contention of the udp sk_receive_queue lock when the socket is > under flood. > > An ancillary queue is added to the udp socket, and the socket always > tries first to read packets from such queue. If it's empty, we splice > the content from sk_receive_queue into the ancillary queue. > > The first patch introduces some helpers to keep the udp code small, and the > following two implement the ancillary queue strategy. The code is split > to hopefully help the reviewing process. > > The measured overall gain under udp flood is in the 20-35% range depending on > the numa layout and the number of ingress queue used by the relevant nic. > Certainly sounds good, but can you give real reproducible performance numbers including the test that was run?
Tom > On a single numa node host, the peak tput is now reached when the traffic > targeting the udp socket uses multiple nic rx queues, while on current > net-next > the tput always decreases when moving from a single rx queue to multiple ones. > > > Paolo Abeni (3): > net/sock: factor out dequeue/peek with offset code > udp: use a separate rx queue for packet reception > udp: keep the sk_receive_queue held when splicing > > include/linux/skbuff.h | 7 +++ > include/linux/udp.h | 3 + > include/net/sock.h | 4 +- > include/net/udp.h | 9 +-- > include/net/udplite.h | 2 +- > net/core/datagram.c | 90 +++++++++++++++------------ > net/ipv4/udp.c | 162 > +++++++++++++++++++++++++++++++++++++++++++------ > net/ipv6/udp.c | 3 +- > 8 files changed, 211 insertions(+), 69 deletions(-) > > -- > 2.9.3 >
