linux-stable/net/tipc
Jon Maloy c0bceb97db tipc: add smart nagle feature
We introduce a feature that works like a combination of TCP_NAGLE and
TCP_CORK, but without some of the weaknesses of those. In particular,
we will not observe long delivery delays because of delayed acks, since
the algorithm itself decides if and when acks are to be sent from the
receiving peer.

- The nagle property as such is determined by manipulating a new
  'maxnagle' field in struct tipc_sock. If certain conditions are met,
  'maxnagle' will define max size of the messages which can be bundled.
  If it is set to zero no messages are ever bundled, implying that the
  nagle property is disabled.
- A socket with the nagle property enabled enters nagle mode when more
  than 4 messages have been sent out without receiving any data message
  from the peer.
- A socket leaves nagle mode whenever it receives a data message from
  the peer.

In nagle mode, messages smaller than 'maxnagle' are accumulated in the
socket write queue. The last buffer in the queue is marked with a new
'ack_required' bit, which forces the receiving peer to send a CONN_ACK
message back to the sender upon reception.

The accumulated contents of the write queue is transmitted when one of
the following events or conditions occur.

- A CONN_ACK message is received from the peer.
- A data message is received from the peer.
- A SOCK_WAKEUP pseudo message is received from the link level.
- The write queue contains more than 64 1k blocks of data.
- The connection is being shut down.
- There is no CONN_ACK message to expect. I.e., there is currently
  no outstanding message where the 'ack_required' bit was set. As a
  consequence, the first message added after we enter nagle mode
  is always sent directly with this bit set.

This new feature gives a 50-100% improvement of throughput for small
(i.e., less than MTU size) messages, while it might add up to one RTT
to latency time when the socket is in nagle mode.

Acked-by: Ying Xue <ying.xue@windreiver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-30 12:16:22 -07:00
..
addr.c tipc: initialise addr_trail_end when setting node addresses 2019-08-11 21:40:04 -07:00
addr.h tipc: add 128-bit node identifier 2018-03-23 13:12:18 -04:00
bcast.c tipc: clean up skb list lock handling on send path 2019-08-18 14:01:07 -07:00
bcast.h tipc: fix a null pointer deref 2019-03-21 09:56:55 -07:00
bearer.c tipc: add loopback device tracking 2019-08-08 22:11:39 -07:00
bearer.h tipc: add loopback device tracking 2019-08-08 22:11:39 -07:00
core.c tipc: improve throughput between nodes in netns 2019-10-29 17:55:38 -07:00
core.h tipc: improve throughput between nodes in netns 2019-10-29 17:55:38 -07:00
diag.c tipc: switch to rhashtable iterator 2018-08-29 18:04:54 -07:00
discover.c tipc: improve throughput between nodes in netns 2019-10-29 17:55:38 -07:00
discover.h tipc: some cleanups in the file discover.c 2018-03-23 13:12:17 -04:00
eth_media.c
group.c tipc: clean up skb list lock handling on send path 2019-08-18 14:01:07 -07:00
group.h tipc: extend sock diag for group communication 2018-06-30 21:05:42 +09:00
ib_media.c
Kconfig docs: kbuild: convert docs to ReST and rename to *.rst 2019-06-14 14:21:21 -06:00
link.c tipc: Spelling s/enpoint/endpoint/ 2019-10-28 13:42:17 -07:00
link.h tipc: fix missing Name entries due to half-failover 2019-05-04 00:59:51 -04:00
Makefile tipc: enable tracepoints in tipc 2018-12-19 11:49:24 -08:00
monitor.c netlink: make nla_nest_start() add NLA_F_NESTED flag 2019-04-27 17:03:44 -04:00
monitor.h tipc: dump monitor attributes 2016-07-26 14:26:42 -07:00
msg.c tipc: add smart nagle feature 2019-10-30 12:16:22 -07:00
msg.h tipc: add smart nagle feature 2019-10-30 12:16:22 -07:00
name_distr.c tipc: improve throughput between nodes in netns 2019-10-29 17:55:38 -07:00
name_distr.h tipc: permit overlapping service ranges in name table 2018-03-31 22:19:52 -04:00
name_table.c netlink: make nla_nest_start() add NLA_F_NESTED flag 2019-04-27 17:03:44 -04:00
name_table.h tipc: eliminate message disordering during binding table update 2018-10-22 19:29:12 -07:00
net.c netlink: make validation more configurable for future strictness 2019-04-27 17:07:21 -04:00
net.h tipc: fix lockdep warning when reinitilaizing sockets 2018-11-17 22:01:31 -08:00
netlink.c net: tipc: allocate attrs locally instead of using genl_family_attrbuf in compat_dumpit() 2019-10-06 15:44:47 +02:00
netlink.h net: tipc: allocate attrs locally instead of using genl_family_attrbuf in compat_dumpit() 2019-10-06 15:44:47 +02:00
netlink_compat.c net: tipc: prepare attrs in __tipc_nl_compat_dumpit() 2019-10-08 18:01:45 -07:00
node.c tipc: improve throughput between nodes in netns 2019-10-29 17:55:38 -07:00
node.h tipc: add smart nagle feature 2019-10-30 12:16:22 -07:00
socket.c tipc: add smart nagle feature 2019-10-30 12:16:22 -07:00
socket.h tipc: add trace_events for tipc socket 2018-12-19 11:49:24 -08:00
subscr.c tipc: fix unbalanced reference counter 2018-04-12 21:46:10 -04:00
subscr.h tipc: fix modprobe tipc failed after switch order of device registration 2019-05-20 10:45:43 -07:00
sysctl.c proc/sysctl: add shared variables for range check 2019-07-18 17:08:07 -07:00
topsrv.c tipc: add loopback device tracking 2019-08-08 22:11:39 -07:00
topsrv.h tipc: rename tipc_server to tipc_topsrv 2018-02-16 15:26:34 -05:00
trace.c tipc: remove unneeded semicolon in trace.c 2019-01-17 22:04:43 -08:00
trace.h tipc: add trace_events for tipc bearer 2018-12-19 11:49:25 -08:00
udp_media.c net: tipc: have genetlink code to parse the attrs during dumpit 2019-10-06 15:44:47 +02:00
udp_media.h tipc: implement configuration of UDP media MTU 2018-04-20 11:04:05 -04:00