rxrpc: Adjust retransmission backoff
Improve retransmission backoff by only backing off when we retransmit data packets rather than when we set the lost ack timer. To this end: (1) In rxrpc_resend(), use rxrpc_get_rto_backoff() when setting the retransmission timer and only tell it that we are retransmitting if we actually have things to retransmit. Note that it's possible for the retransmission algorithm to race with the processing of a received ACK, so we may see no packets needing retransmission. (2) In rxrpc_send_data_packet(), don't bump the backoff when setting the ack_lost_at timer, as it may then get bumped twice. With this, when looking at one particular packet, the retransmission intervals were seen to be 1.5ms, 2ms, 3ms, 5ms, 9ms, 17ms, 33ms, 71ms, 136ms, 264ms, 544ms, 1.088s, 2.1s, 4.2s and 8.3s. Fixes: c410bf01 ("rxrpc: Fix the excessive initial retransmission timeout") Suggested-by:Marc Dionne <marc.dionne@auristor.com> Signed-off-by:
David Howells <dhowells@redhat.com> Reviewed-by:
Marc Dionne <marc.dionne@auristor.com> Tested-by:
Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org Link: https://lore.kernel.org/r/164138117069.2023386.17446904856843997127.stgit@warthog.procyon.org.uk/ Signed-off-by:
David S. Miller <davem@davemloft.net>
parent
03c82e80
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