linux/include
Yuchung Cheng 7e901ee7b6 tcp: avoid slow start during fast recovery on new losses
During TCP fast recovery, the congestion control in charge is by
default the Proportional Rate Reduction (PRR) unless the congestion
control module specified otherwise (e.g. BBR).

Previously when tcp_packets_in_flight() is below snd_ssthresh PRR
would slow start upon receiving an ACK that
   1) cumulatively acknowledges retransmitted data
   and
   2) does not detect further lost retransmission

Such conditions indicate the repair is in good steady progress
after the first round trip of recovery. Otherwise PRR adopts the
packet conservation principle to send only the amount that was
newly delivered (indicated by this ACK).

This patch generalizes the previous design principle to include
also the newly sent data beside retransmission: as long as
the delivery is making good progress, both retransmission and
new data should be accounted to make PRR more cautious in slow
starting.

Suggested-by: Matt Mathis <mattmathis@google.com>
Suggested-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20201031013412.1973112-1-ycheng@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-02 17:17:40 -08:00
..
acpi pci-v5.10-changes 2020-10-22 12:41:00 -07:00
asm-generic vmlinux.lds.h: Keep .ctors.* with .ctors 2020-10-27 11:13:41 -07:00
clocksource clocksource/drivers/sp804: Remove unused sp804_timer_disable() and timer-sp804.h 2020-09-24 10:51:04 +02:00
crypto X.509: Fix modular build of public_key_sm2 2020-10-08 16:39:14 +11:00
drm sound updates for 5.10 2020-10-15 11:07:44 -07:00
dt-bindings ARM: Devicetree updates 2020-10-24 10:44:18 -07:00
keys
kunit treewide: Convert macro and uses of __section(foo) to __section("foo") 2020-10-25 14:51:49 -07:00
kvm ARM: 2020-10-23 11:17:56 -07:00
linux net: core: add devm_netdev_alloc_pcpu_stats 2020-10-31 10:22:49 -07:00
math-emu
media ARM: SoC platform updates 2020-10-24 10:33:08 -07:00
memory
misc
net tcp: avoid slow start during fast recovery on new losses 2020-11-02 17:17:40 -08:00
pcmcia
ras mm,hwpoison: introduce MF_MSG_UNSPLIT_THP 2020-10-16 11:11:17 -07:00
rdma RDMA: Add rdma_connect_locked() 2020-10-28 09:14:49 -03:00
scsi SCSI misc on 20201023 2020-10-23 16:19:02 -07:00
soc net: mscc: ocelot: deny changing the native VLAN from the prepare phase 2020-11-02 17:09:07 -08:00
sound ASoC: Updates for v5.10 2020-10-12 16:08:57 +02:00
target
trace afs: Fix afs_invalidatepage to adjust the dirty region 2020-10-29 13:53:04 +00:00
uapi net: bridge: mcast: add support for raw L2 multicast groups 2020-10-30 17:49:19 -07:00
vdso
video
xen xen: branch for v5.10-rc1c 2020-10-25 10:55:35 -07:00