From: Jakub Kicinski Date: Thu, 15 May 2025 18:30:11 +0000 (-0700) Subject: Merge branch 'tcp-receive-side-improvements' X-Git-Tag: v6.16-rc1~132^2~97 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2da35e4b4df99d3dd29bacf0c054e6988013d4ec;p=thirdparty%2Flinux.git Merge branch 'tcp-receive-side-improvements' Eric Dumazet says: ==================== tcp: receive side improvements We have set tcp_rmem[2] to 15 MB for about 8 years at Google, but had some issues for high speed flows on very small RTT. TCP rx autotuning has a tendency to overestimate the RTT, thus tp->rcvq_space.space and sk->sk_rcvbuf. This makes TCP receive queues much bigger than necessary, to a point cpu caches are evicted before application can copy the data, on cpus using DDIO. This series aims to fix this. - First patch adds tcp_rcvbuf_grow() tracepoint, which was very convenient to study the various issues fixed in this series. - Seven patches fix receiver autotune issues. - Two patches fix sender side issues. - Final patch increases tcp_rmem[2] so that TCP speed over WAN can meet modern needs. Tested on a 200Gbit NIC, average max throughput of a single flow: Before: 73593 Mbit. After: 122514 Mbit. ==================== Link: https://patch.msgid.link/20250513193919.1089692-1-edumazet@google.com Signed-off-by: Jakub Kicinski --- 2da35e4b4df99d3dd29bacf0c054e6988013d4ec