summaryrefslogtreecommitdiff
path: root/net/rxrpc
diff options
context:
space:
mode:
authorDavid Howells <dhowells@redhat.com>2023-02-01 00:40:18 +0300
committerDavid Howells <dhowells@redhat.com>2023-02-08 02:11:21 +0300
commit5a2c5a5b0829ef8bcb5d868145c1d8c1221c5637 (patch)
tree441da5c8f36a3c989c34f698746e1a00ff993976 /net/rxrpc
parentf789bff2deb3ddae08950f8e4a1e6f41b916c520 (diff)
downloadlinux-5a2c5a5b0829ef8bcb5d868145c1d8c1221c5637.tar.xz
rxrpc: Reduce unnecessary ack transmission
rxrpc_recvmsg_data() schedules an ACK to be transmitted every time at least two packets have been consumed and any time it runs out of data and would return -EAGAIN to the caller. Both events may occur within a single loop, however, and if the I/O thread is quick enough it may send duplicate ACKs. The ACKs are sent to inform the peer that more space has been made in the local Rx window, but the I/O thread is going to send an ACK every couple of DATA packets anyway, so we end up sending a lot more ACKs than we really need to. So reduce the rate at which recvmsg() schedules ACKs, such that if the I/O thread sends ACKs at its normal faster rate, recvmsg() won't actually schedule ACKs until the Rx flow stops (call->rx_consumed is cleared any time we transmit an ACK for that call, resetting the counter used by recvmsg). Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
Diffstat (limited to 'net/rxrpc')
-rw-r--r--net/rxrpc/recvmsg.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/net/rxrpc/recvmsg.c b/net/rxrpc/recvmsg.c
index 50d263a6359d..76eb2b9cd936 100644
--- a/net/rxrpc/recvmsg.c
+++ b/net/rxrpc/recvmsg.c
@@ -137,7 +137,7 @@ static void rxrpc_rotate_rx_window(struct rxrpc_call *call)
/* Check to see if there's an ACK that needs sending. */
acked = atomic_add_return(call->rx_consumed - old_consumed,
&call->ackr_nr_consumed);
- if (acked > 2 &&
+ if (acked > 8 &&
!test_and_set_bit(RXRPC_CALL_RX_IS_IDLE, &call->flags))
rxrpc_poke_call(call, rxrpc_call_poke_idle);
}