]> git.baikalelectronics.ru Git - kernel.git/commit
sctp: adjust ssthresh when transport is idle
authorMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Fri, 23 Jun 2017 22:59:36 +0000 (19:59 -0300)
committerDavid S. Miller <davem@davemloft.net>
Sun, 25 Jun 2017 18:43:53 +0000 (14:43 -0400)
commit694671b0ca76ceb72c8b87d16d03de1365d4e83c
treef279d0fb0ffba67245fba656819e128a2f2fee02
parentb3ef0c88860819568f1b070fa6a54eb649febea0
sctp: adjust ssthresh when transport is idle

RFC 4960 Errata 3.27 identifies that ssthresh should be adjusted to cwnd
because otherwise it could cause the transport to lock into congestion
avoidance phase specially if ssthresh was previously reduced by some
packet drop, leading to poor performance.

The Errata says to adjust ssthresh to cwnd only once, though the same
goal is achieved by updating it every time we update cwnd too. The
caveat is that we could take longer to get back up to speed but that
should be compensated by the fact that we don't adjust on RTO basis (as
RFC says) but based on Heartbeats, which are usually way longer.

See-also: https://tools.ietf.org/html/draft-ietf-tsvwg-rfc4960-errata-01#section-3.27
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/sctp/transport.c