Commit "odp: Support conntrack orig tuple key." introduced new fields in struct 'pkt_metadata'. pkt_metadata_init() is called for every packet in the userspace datapath. When testing a simple single flow case with DPDK, we observe a lower throughput after the above commit (it was 14.88 Mpps before, it is 13 Mpps after).
This patch skips initializing ct_orig_tuple in pkt_metadata_init(). It should be enough to initialize ct_state, because nobody should look at ct_orig_tuple unless ct_state is != 0. It's discussed at: https://mail.openvswitch.org/pipermail/ovs-dev/2017-May/332419.html Fixes: daf4d3c18da4("odp: Support conntrack orig tuple key.") Signed-off-by: Daniele Di Proietto <diproiet...@vmware.com> Signed-off-by: Bhanuprakash Bodireddy <bhanuprakash.bodire...@intel.com> Co-authored-by: Bhanuprakash Bodireddy <bhanuprakash.bodire...@intel.com> --- Original RFC was posted by Daniele here: https://mail.openvswitch.org/pipermail/ovs-dev/2017-March/329679.html In this patch moved the offset from ct_orig_tuple to 'ct_orig_tuple_ipv6'. This patch fixes the performance drop(~2.3Mpps for P2P - 64 byte pkts) with OvS-DPDK on Master. lib/packets.h | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/lib/packets.h b/lib/packets.h index a9d5e84..94c3dcc 100644 --- a/lib/packets.h +++ b/lib/packets.h @@ -126,10 +126,19 @@ pkt_metadata_init_tnl(struct pkt_metadata *md) static inline void pkt_metadata_init(struct pkt_metadata *md, odp_port_t port) { + /* This is called for every packet in userspace datapath and affects + * performance if all the metadata is initialized. Hence absolutely + * necessary fields should be zeroed out. + * + * Initialize only the first 17 bytes of metadata (till ct_state). + * Once the ct_state is zeroed out rest of ct fields will not be looked + * at unless ct_state != 0. + */ + memset(md, 0, offsetof(struct pkt_metadata, ct_orig_tuple_ipv6)); + /* It can be expensive to zero out all of the tunnel metadata. However, * we can just zero out ip_dst and the rest of the data will never be * looked at. */ - memset(md, 0, offsetof(struct pkt_metadata, in_port)); md->tunnel.ip_dst = 0; md->tunnel.ipv6_dst = in6addr_any; md->in_port.odp_port = port; -- 2.4.11 _______________________________________________ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev
