Hi Eric, On Sat, 2016-12-03 at 11:14 -0800, Eric Dumazet wrote: > Group fields used in TX path, and keep some cache lines mostly read > to permit sharing among cpus. > > Gained two 4 bytes holes on 64bit arches. > > Added a place holder for tcp tsq_flags, next to sk_wmem_alloc > to speed up tcp_wfree() in the following patch. > > I have not added ____cacheline_aligned_in_smp, this might be done later. > I prefer doing this once inet and tcp/udp sockets reorg is also done. > > Tested with both TCP and UDP. > > UDP receiver performance under flood increased by ~20 % : > Accessing sk_filter/sk_wq/sk_napi_id no longer stalls because sk_drops > was moved away from a critical cache line, now mostly read and shared.
I cherry-picked this patch only for some UDP benchmark. Under flood with many concurrent flows, I see this 20% improvement and a relevant decrease in system load. Nice work, thanks Eric! Tested-by: Paolo Abeni <pab...@redhat.com>
