Sub optimal behaviour with TCP over PPP in 2.1.103?

Roderich Schupp (rsch@ExperTeam.de)
Sat, 23 May 1998 21:29:27 +0200

Hi,
while I was looking for another problem I wondered if the
following tcpdump really shows the behaviour one would expect.
This is part of smbclient session from Linux 2.1.103 to an NT4.0
RAS server. This session runs over PPP on a 14400baud modem connection.
The tcpdump shows an upload of a 120K file to NT. Note
the frequent retransmissions of packets recently ack'ed
and the burst of packets at the start.
So is this OK, NT's fault, bad configuration (use smaller MTU?) or what?
Cheers, Roderich

18:00:47.898759 linux.1050 > nt4-ras.netbios-ssn: S 483671187:483671187(0)
win 31856 <mss 1460,sackOK,timestamp 2268091 0,nop,wscale 0> (DF)
18:00:48.178759 nt4-ras.netbios-ssn > linux.1050: S 287211203:287211203(0)
ack 483671188 win 8760 <mss 1460> (DF)
18:00:48.178759 linux.1050 > nt4-ras.netbios-ssn: . ack 1 win 31856 (DF)
18:00:48.258759 linux.1050 > nt4-ras.netbios-ssn: P 1:77(76) ack 1 win
31856 (DF)
18:00:48.528759 nt4-ras.netbios-ssn > linux.1050: P 1:5(4) ack 77 win 8684
(DF)
18:00:48.548759 linux.1050 > nt4-ras.netbios-ssn: . ack 5 win 31856 (DF)
18:00:48.558759 linux.1050 > nt4-ras.netbios-ssn: P 77:245(168) ack 5 win
31856 (DF)
18:00:48.938759 nt4-ras.netbios-ssn > linux.1050: P 5:104(99) ack 245 win
8516 (DF)
18:00:48.958759 linux.1050 > nt4-ras.netbios-ssn: . ack 104 win 31856 (DF)
18:00:49.088759 linux.1050 > nt4-ras.netbios-ssn: P 245:360(115) ack 104
win 31856 (DF)
18:00:49.448759 nt4-ras.netbios-ssn > linux.1050: P 104:192(88) ack 360 win
8401 (DF)
18:00:49.468759 linux.1050 > nt4-ras.netbios-ssn: . ack 192 win 31856 (DF)
18:00:49.538759 linux.1050 > nt4-ras.netbios-ssn: P 360:427(67) ack 192 win
31856 (DF)
18:00:49.848759 nt4-ras.netbios-ssn > linux.1050: P 192:245(53) ack 427 win
8334 (DF)
18:00:49.868759 linux.1050 > nt4-ras.netbios-ssn: . ack 245 win 31856 (DF)
18:01:04.848759 linux.1050 > nt4-ras.netbios-ssn: P 427:477(50) ack 245 win
31856 (DF)
18:01:05.158759 nt4-ras.netbios-ssn > linux.1050: P 245:284(39) ack 477 win
8284 (DF)
18:01:05.178759 linux.1050 > nt4-ras.netbios-ssn: . ack 284 win 31856 (DF)
18:01:20.818759 linux.1050 > nt4-ras.netbios-ssn: P 477:535(58) ack 284 win
31856 (DF)
18:01:21.128759 nt4-ras.netbios-ssn > linux.1050: P 284:325(41) ack 535 win
8226 (DF)
18:01:21.148759 linux.1050 > nt4-ras.netbios-ssn: . ack 325 win 31856 (DF)
18:01:21.278759 linux.1050 > nt4-ras.netbios-ssn: P 535:598(63) ack 325 win
31856 (DF)
18:01:21.558759 nt4-ras.netbios-ssn > linux.1050: P 325:366(41) ack 598 win
8163 (DF)
18:01:21.578759 linux.1050 > nt4-ras.netbios-ssn: . ack 366 win 31856 (DF)
[ This is where the "put file" really starts. Note that smbclient
actually writes one 64K SMB packet in one write syscall.]
18:01:21.588759 linux.1050 > nt4-ras.netbios-ssn: . 598:2058(1460) ack 366
win 31856 (DF)
18:01:21.588759 linux.1050 > nt4-ras.netbios-ssn: . 2058:3518(1460) ack 366
win 31856 (DF)
18:01:21.588759 linux.1050 > nt4-ras.netbios-ssn: . 3518:4978(1460) ack 366
win 31856 (DF)
18:01:21.588759 linux.1050 > nt4-ras.netbios-ssn: . 4978:6438(1460) ack 366
win 31856 (DF)
18:01:21.778759 linux.1050 > nt4-ras.netbios-ssn: . 4978:6438(1460) ack 366
win 31856 (DF)
18:01:21.778759 linux.1050 > nt4-ras.netbios-ssn: . 6438:7898(1460) ack 366
win 31856 (DF)
18:01:22.528759 linux.1050 > nt4-ras.netbios-ssn: . 6438:7898(1460) ack 366
win 31856 (DF)
18:01:22.528759 linux.1050 > nt4-ras.netbios-ssn: . 598:2058(1460) ack 366
win 31856 (DF)
18:01:22.818759 nt4-ras.netbios-ssn > linux.1050: . ack 2058 win 8760 (DF)
18:01:23.428759 linux.1050 > nt4-ras.netbios-ssn: . 598:2058(1460) ack 366
win 31856 (DF)
18:01:23.428759 linux.1050 > nt4-ras.netbios-ssn: . 2058:3518(1460) ack 366
win 31856 (DF)
18:01:23.658759 nt4-ras.netbios-ssn > linux.1050: . ack 3518 win 8760 (DF)
18:01:24.328759 linux.1050 > nt4-ras.netbios-ssn: . 2058:3518(1460) ack 366
win 31856 (DF)
18:01:24.328759 linux.1050 > nt4-ras.netbios-ssn: . 3518:4978(1460) ack 366
win 31856 (DF)
18:01:24.558759 nt4-ras.netbios-ssn > linux.1050: . ack 4978 win 8760 (DF)
18:01:25.248759 linux.1050 > nt4-ras.netbios-ssn: . 3518:4978(1460) ack 366
win 31856 (DF)
18:01:25.248759 linux.1050 > nt4-ras.netbios-ssn: . 4978:6438(1460) ack 366
win 31856 (DF)
18:01:25.398759 nt4-ras.netbios-ssn > linux.1050: . ack 6438 win 8760 (DF)
18:01:26.008759 linux.1050 > nt4-ras.netbios-ssn: . 4978:6438(1460) ack 366
win 31856 (DF)
18:01:26.008759 linux.1050 > nt4-ras.netbios-ssn: . 6438:7898(1460) ack 366
win 31856 (DF)
18:01:26.308759 nt4-ras.netbios-ssn > linux.1050: . ack 7898 win 8760 (DF)
18:01:26.908759 linux.1050 > nt4-ras.netbios-ssn: . 6438:7898(1460) ack 366
win 31856 (DF)
18:01:26.908759 linux.1050 > nt4-ras.netbios-ssn: . 7898:9358(1460) ack 366
win 31856 (DF)
18:01:27.048759 nt4-ras.netbios-ssn > linux.1050: . ack 7898 win 8760 (DF)
18:01:27.798759 linux.1050 > nt4-ras.netbios-ssn: . 7898:9358(1460) ack 366
win 31856 (DF)
18:01:27.818759 linux.1050 > nt4-ras.netbios-ssn: . 7898:9358(1460) ack 366
win 31856 (DF)
18:01:27.888759 nt4-ras.netbios-ssn > linux.1050: . ack 7898 win 8760 (DF)
18:01:28.698759 linux.1050 > nt4-ras.netbios-ssn: . 7898:9358(1460) ack 366
win 31856 (DF)
18:01:28.798759 nt4-ras.netbios-ssn > linux.1050: . ack 7898 win 8760 (DF)
18:01:29.638759 nt4-ras.netbios-ssn > linux.1050: . ack 7898 win 8760 (DF)
18:01:30.548759 nt4-ras.netbios-ssn > linux.1050: . ack 7898 win 8760 (DF)
18:01:30.818759 linux.1050 > nt4-ras.netbios-ssn: . 7898:9358(1460) ack 366
win 31856 (DF)
18:01:31.558759 nt4-ras.netbios-ssn > linux.1050: . ack 9358 win 8760 (DF)

--
         Franz jagt im komplett verwahrlosten Taxi quer durch Bayern.
Roderich Schupp                 mailto:rsch@ExperTeam.de
ExperTeam GmbH                  http://www.experteam.de/
Munich, Germany                 linux:2.1.103






-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu