From 4d3c46e6833208428d366630aa708f6876e61fc1 Mon Sep 17 00:00:00 2001 From: Vlad Yasevich Date: Fri, 4 Sep 2009 18:20:59 -0400 Subject: sctp: drop a_rwnd to 0 when receive buffer overflows. SCTP has a problem that when small chunks are used, it is possible to exhaust the receiver buffer without fully closing receive window. This happens due to all overhead that we have account for with small messages. To fix this, when receive buffer is exceeded, we'll drop the window to 0 and save the 'drop' portion. When application starts reading data and freeing up recevie buffer space, we'll wait until we've reached the 'drop' window and then add back this 'drop' one mtu at a time. This worked well in testing and under stress produced rather even recovery. Signed-off-by: Vlad Yasevich --- include/net/sctp/structs.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'include') diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h index 97024faaa08..b1bd2689bb7 100644 --- a/include/net/sctp/structs.h +++ b/include/net/sctp/structs.h @@ -1739,6 +1739,12 @@ struct sctp_association { */ __u32 rwnd_over; + /* Keeps treack of rwnd pressure. This happens when we have + * a window, but not recevie buffer (i.e small packets). This one + * is releases slowly (1 PMTU at a time ). + */ + __u32 rwnd_press; + /* This is the sndbuf size in use for the association. * This corresponds to the sndbuf size for the association, * as specified in the sk->sndbuf. -- cgit v1.2.3