[SCTP]: Include sk_buff overhead while updating the peer's receive window.

Currently if the sender is sending small messages, it can cause a receiver
to run out of receive buffer space even when the advertised receive window
is still open and results in packet drops and retransmissions. Including
a overhead while updating the sender's view of peer receive window will
reduce the chances of receive buffer space overshooting the receive window.

Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Sridhar Samudrala 2006-09-29 17:09:05 -07:00 committed by David S. Miller
parent 208edef6a5
commit cd49788563
2 changed files with 10 additions and 3 deletions

View file

@ -633,7 +633,7 @@ static sctp_xmit_t sctp_packet_append_data(struct sctp_packet *packet,
* data will fit or delay in hopes of bundling a full
* sized packet.
*/
if (len < asoc->pathmtu - packet->overhead) {
if (len < asoc->frag_point) {
retval = SCTP_XMIT_NAGLE_DELAY;
goto finish;
}
@ -645,7 +645,13 @@ static sctp_xmit_t sctp_packet_append_data(struct sctp_packet *packet,
/* Keep track of how many bytes are in flight to the receiver. */
asoc->outqueue.outstanding_bytes += datasize;
/* Update our view of the receiver's rwnd. */
/* Update our view of the receiver's rwnd. Include sk_buff overhead
* while updating peer.rwnd so that it reduces the chances of a
* receiver running out of receive buffer space even when receive
* window is still open. This can happen when a sender is sending
* sending small messages.
*/
datasize += sizeof(struct sk_buff);
if (datasize < rwnd)
rwnd -= datasize;
else

View file

@ -416,7 +416,8 @@ void sctp_retransmit_mark(struct sctp_outq *q,
* (Section 7.2.4)), add the data size of those
* chunks to the rwnd.
*/
q->asoc->peer.rwnd += sctp_data_size(chunk);
q->asoc->peer.rwnd += (sctp_data_size(chunk) +
sizeof(struct sk_buff));
q->outstanding_bytes -= sctp_data_size(chunk);
transport->flight_size -= sctp_data_size(chunk);