On Tue, Jan 11, 2022 at 11:29 AM Ivan Babrou <ivan@xxxxxxxxxxxxxx> wrote: > > This patch adds bpf_setsockopt(TCP_BPF_RCV_SSTHRESH) to allow setting > rcv_ssthresh value for TCP connections. Combined with increased > window_clamp via tcp_rmem[1], it allows to advertise initial scaled > TCP window larger than 64k. This is useful for high BDP connections, > where it allows to push data with fewer roundtrips, reducing latency. > > For active connections the larger window is advertised in the first > non-SYN ACK packet as the part of the 3 way handshake. > > For passive connections the larger window is advertised whenever > there's any packet to send after the 3 way handshake. > > See: https://lkml.org/lkml/2021/12/22/652 I guess this is [1] mentioned above. Please use lore link instead, e.g. [1] https://lore.kernel.org/all/CABWYdi0qBQ57OHt4ZbRxMtdSzhubzkPaPKkYzdNfu4+cgPyXCA@xxxxxxxxxxxxxx/ Can we add a selftests for this? Something similar to tools/testing/selftests/bpf/progs/test_misc_tcp_hdr_options.c Thanks, Song [...]
