Searched hist:11707 (Results 1 - 2 of 2) sorted by relevance

/linux-master/net/ipv4/
H A Dtcp_cubic.cdiff 42f3a8aa Mon Dec 23 01:27:53 MST 2019 Eric Dumazet <edumazet@google.com> tcp_cubic: tweak Hystart detection for short RTT flows

After switching ca->delay_min to usec resolution, we exit
slow start prematurely for very low RTT flows, setting
snd_ssthresh to 20.

The reason is that delay_min is fed with RTT of small packet
trains. Then as cwnd is increased, TCP sends bigger TSO packets.

LRO/GRO aggregation and/or interrupt mitigation strategies
on receiver tend to inflate RTT samples.

Fix this by adding to delay_min the expected delay of
two TSO packets, given current pacing rate.

Tested:

Sender uses pfifo_fast qdisc

Before :
$ nstat -n;for f in {1..10}; do ./super_netperf 1 -H lpaa24 -l -4000000; done;nstat|egrep "Hystart"
11348
11707
11562
11428
11773
11534
9878
11693
10597
10968
TcpExtTCPHystartTrainDetect 10 0.0
TcpExtTCPHystartTrainCwnd 200 0.0

After :
$ nstat -n;for f in {1..10}; do ./super_netperf 1 -H lpaa24 -l -4000000; done;nstat|egrep "Hystart"
14877
14517
15797
18466
17376
14833
17558
17933
16039
18059
TcpExtTCPHystartTrainDetect 10 0.0
TcpExtTCPHystartTrainCwnd 1670 0.0

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
/linux-master/fs/gfs2/
H A Dbmap.cdiff 11707ea0 Mon Jan 28 08:10:29 MST 2008 Steven Whitehouse <swhiteho@redhat.com> [GFS2] Move part of gfs2_block_map into a separate function

This is required to enable future changes to the block
mapping code.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

Completed in 148 milliseconds