TSO and FreeBSD vs Linux

David Wolfskill david at catwhisker.org
Wed Sep 4 22:35:59 UTC 2013


On Wed, Sep 04, 2013 at 03:25:59PM -0700, Adrian Chadd wrote:
> What's netstat -sp tcp show before/after the test?
> ...

Typescript attached.

Peace,
david
-- 
David H. Wolfskill				david at catwhisker.org
Taliban: Evil cowards with guns afraid of truth from a 14-year old girl.

See http://www.catwhisker.org/~david/publickey.gpg for my public key.
-------------- next part --------------
Script started on Wed Sep  4 15:31:50 2013
dwolf-fbsd(9.2-P)[15] sudo sysctl net.inet.tcp.tso=1

Password:
net.inet.tcp.tso: 0 -> 1
dwolf-fbsd(9.2-P)[16] netstat -sp tcp

tcp:
	2555593963 packets sent
		4800252 data packets (2675428399 bytes)
		2547149487 data packets (7491423231574 bytes) retransmitted
		12755 data packets unnecessarily retransmitted
		2546909891 resends initiated by MTU discovery
		3630427 ack-only packets (270271 delayed)
		0 URG only packets
		0 window probe packets
		2596 window update packets
		3453 control packets
	10886789 packets received
		3928645 acks (for 2807958913 bytes)
		26320 duplicate acks
		0 acks for unsent data
		9070321 packets (9528490768 bytes) received in-sequence
		574 completely duplicate packets (128517 bytes)
		2 old duplicate packets
		104 packets with some dup. data (4084 bytes duped)
		90 out-of-order packets (99414 bytes)
		833 packets (833 bytes) of data after window
		833 window probes
		25734 window update packets
		6 packets received after close
		0 discarded for bad checksums
		0 discarded for bad header offset fields
		0 discarded because packet too short
		0 discarded due to memory problems
	1677 connection requests
	315 connection accepts
	0 bad connection attempts
	0 listen queue overflows
	6 ignored RSTs in the windows
	1933 connections established (including accepts)
	2298 connections closed (including 90 drops)
		1458 connections updated cached RTT on close
		1460 connections updated cached RTT variance on close
		900 connections updated cached ssthresh on close
	32 embryonic connections dropped
	3928644 segments updated rtt (of 2914696 attempts)
	128226 retransmit timeouts
		2 connections dropped by rexmit timeout
	0 persist timeouts
		0 connections dropped by persist timeout
	0 Connections (fin_wait_2) dropped because of timeout
	163 keepalive timeouts
		153 keepalive probes sent
		10 connections dropped by keepalive
	482733 correct ACK header predictions
	6883177 correct data packet header predictions
	315 syncache entries added
		0 retransmitted
		0 dupsyn
		0 dropped
		315 completed
		0 bucket overflow
		0 cache overflow
		0 reset
		0 stale
		0 aborted
		0 badack
		0 unreach
		0 zone failures
	315 cookies sent
	0 cookies received
	194 hostcache entries added
		0 bucket overflow
	1802 SACK recovery episodes
	3576 segment rexmits in SACK recovery episodes
	4987584 byte rexmits in SACK recovery episodes
	51765 SACK options (SACK blocks) received
	74 SACK options (SACK blocks) sent
	0 SACK scoreboard overflow
	0 packets with ECN CE bit set
	0 packets with ECN ECT(0) bit set
	0 packets with ECN ECT(1) bit set
	0 successful ECN handshakes
	0 times ECN reduced the congestion window
dwolf-fbsd(9.2-P)[17] cp ~/Mail/sisyphus ~/tmp

^C^C

dwolf-fbsd(9.2-P)[18] ls -lT !$/sisyphus

ls -lT ~/tmp/sisyphus
^Cdwolf-fbsd(9.2-P)[19] ls -lT ~/tmp/sisyphus

-rw-------  1 dwolf  929  1048576 Sep  4 15:32:31 2013 /homes/dwolf/tmp/sisyphus
dwolf-fbsd(9.2-P)[20] ls -lT ~/tmp/sisyphuscp ~/Mail/sisyphus ~/tmpnetstat -sp tcp

tcp:
	2560478331 packets sent
		4800896 data packets (2676331641 bytes)
		2552032761 data packets (7507101784670 bytes) retransmitted
		12860 data packets unnecessarily retransmitted
		2551792768 resends initiated by MTU discovery
		3630851 ack-only packets (270311 delayed)
		0 URG only packets
		0 window probe packets
		2596 window update packets
		3479 control packets
	10888714 packets received
		3929168 acks (for 2808876755 bytes)
		26579 duplicate acks
		0 acks for unsent data
		9071336 packets (9529611537 bytes) received in-sequence
		582 completely duplicate packets (129829 bytes)
		2 old duplicate packets
		104 packets with some dup. data (4084 bytes duped)
		90 out-of-order packets (99414 bytes)
		833 packets (833 bytes) of data after window
		833 window probes
		25915 window update packets
		7 packets received after close
		0 discarded for bad checksums
		0 discarded for bad header offset fields
		0 discarded because packet too short
		0 discarded due to memory problems
	1703 connection requests
	315 connection accepts
	0 bad connection attempts
	0 listen queue overflows
	6 ignored RSTs in the windows
	1934 connections established (including accepts)
	2325 connections closed (including 90 drops)
		1459 connections updated cached RTT on close
		1461 connections updated cached RTT variance on close
		901 connections updated cached ssthresh on close
	32 embryonic connections dropped
	3929167 segments updated rtt (of 2915199 attempts)
	128468 retransmit timeouts
		2 connections dropped by rexmit timeout
	0 persist timeouts
		0 connections dropped by persist timeout
	0 Connections (fin_wait_2) dropped because of timeout
	163 keepalive timeouts
		153 keepalive probes sent
		10 connections dropped by keepalive
	482835 correct ACK header predictions
	6884084 correct data packet header predictions
	315 syncache entries added
		0 retransmitted
		0 dupsyn
		0 dropped
		315 completed
		0 bucket overflow
		0 cache overflow
		0 reset
		0 stale
		0 aborted
		0 badack
		0 unreach
		0 zone failures
	315 cookies sent
	0 cookies received
	195 hostcache entries added
		0 bucket overflow
	1843 SACK recovery episodes
	3648 segment rexmits in SACK recovery episodes
	5090892 byte rexmits in SACK recovery episodes
	52227 SACK options (SACK blocks) received
	74 SACK options (SACK blocks) sent
	0 SACK scoreboard overflow
	0 packets with ECN CE bit set
	0 packets with ECN ECT(0) bit set
	0 packets with ECN ECT(1) bit set
	0 successful ECN handshakes
	0 times ECN reduced the congestion window
dwolf-fbsd(9.2-P)[21] netstat -sp tcpls -lT ~/tmp/sisyphuscp ~/Mail/sisyphus ~/tmpnetstat -sp tcpsudo sysctl net.inet.tcp.tso=10

net.inet.tcp.tso: 1 -> 0
dwolf-fbsd(9.2-P)[22] sudo sysctl net.inet.tcp.tso=0netstat -sp tcpls -lT ~/tmp/sisyphuscp ~/Mail/sisyphus ~/tmp

dwolf-fbsd(9.2-P)[23] echo $?

0
dwolf-fbsd(9.2-P)[24] echo $?cp ~/Mail/sisyphus ~/tmpsudo sysctl net.inet.tcp.tso=0netstat -sp tcpls -lT ~/tmp/sisyphus

-rw-------  1 dwolf  929  117836339 Sep  4 15:33:34 2013 /homes/dwolf/tmp/sisyphus
dwolf-fbsd(9.2-P)[25] ls -lT ~/tmp/sisyphusecho $?cp ~/Mail/sisyphus ~/tmpsudo sysctl net.inet.tcp.tso=0netstat -sp tcp

tcp:
	2561662836 packets sent
		4888547 data packets (2797024810 bytes)
		2553088612 data packets (7510826223526 bytes) retransmitted
		12896 data packets unnecessarily retransmitted
		2552848084 resends initiated by MTU discovery
		3671853 ack-only packets (270403 delayed)
		0 URG only packets
		0 window probe packets
		2596 window update packets
		3480 control packets
	11026149 packets received
		3976120 acks (for 2929572833 bytes)
		29410 duplicate acks
		0 acks for unsent data
		9167030 packets (9648083856 bytes) received in-sequence
		597 completely duplicate packets (147049 bytes)
		2 old duplicate packets
		104 packets with some dup. data (4084 bytes duped)
		893 out-of-order packets (1235254 bytes)
		833 packets (833 bytes) of data after window
		833 window probes
		26317 window update packets
		7 packets received after close
		0 discarded for bad checksums
		0 discarded for bad header offset fields
		0 discarded because packet too short
		0 discarded due to memory problems
	1703 connection requests
	315 connection accepts
	0 bad connection attempts
	0 listen queue overflows
	6 ignored RSTs in the windows
	1934 connections established (including accepts)
	2325 connections closed (including 90 drops)
		1460 connections updated cached RTT on close
		1462 connections updated cached RTT variance on close
		901 connections updated cached ssthresh on close
	32 embryonic connections dropped
	3976119 segments updated rtt (of 2960431 attempts)
	128506 retransmit timeouts
		2 connections dropped by rexmit timeout
	0 persist timeouts
		0 connections dropped by persist timeout
	0 Connections (fin_wait_2) dropped because of timeout
	163 keepalive timeouts
		153 keepalive probes sent
		10 connections dropped by keepalive
	519937 correct ACK header predictions
	6970417 correct data packet header predictions
	315 syncache entries added
		0 retransmitted
		0 dupsyn
		0 dropped
		315 completed
		0 bucket overflow
		0 cache overflow
		0 reset
		0 stale
		0 aborted
		0 badack
		0 unreach
		0 zone failures
	315 cookies sent
	0 cookies received
	195 hostcache entries added
		0 bucket overflow
	1945 SACK recovery episodes
	4143 segment rexmits in SACK recovery episodes
	5780288 byte rexmits in SACK recovery episodes
	55903 SACK options (SACK blocks) received
	833 SACK options (SACK blocks) sent
	0 SACK scoreboard overflow
	0 packets with ECN CE bit set
	0 packets with ECN ECT(0) bit set
	0 packets with ECN ECT(1) bit set
	0 successful ECN handshakes
	0 times ECN reduced the congestion window
dwolf-fbsd(9.2-P)[26] ^Dexit

Script done on Wed Sep  4 15:34:54 2013
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 196 bytes
Desc: not available
URL: <http://lists.freebsd.org/pipermail/freebsd-net/attachments/20130904/cbcb1500/attachment.sig>


More information about the freebsd-net mailing list