-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi, Since I updated, a month ago, from SuSE 8.2 to SuSE 9.1 I had the feeling that the modem connection was slower than previously. Previously I saw comments on this list to that effect, but they seemed to be related to winmodems. It could be just an unjustified feeling, therefore I started to pay more attention, and finally I ran some test to confirm it. Thus, I can now confirm it: there is something in SuSE 9.1 that makes Internet connection using a modem definitely slower than previous versions of SuSE. ** System ** SuSE 9.1 on a P-IV at 1.8 Ghz, with 700Mb ram. Internet connection through external serial modem (3COM US Robotics, V90 type) - no winmodem involved. I have tried reducing the TCP window to 8Kb, as recommended on the SDB: no noticeably change. Patches (YOU) are almost up to date - at 2K/s a kernel update is... fearsome :-( Connection is started using wvdial on an xterm (same definitions as in SuSE 8.2 previously). Desktop is gnome. Running susefirewall2 and DNS locally. More info: just ask for it :-) ** Symptoms ** Mail fetching (fetchmail) runs jerkily, it runs and stops, seldom reaching 5Kb/s. It may stop for as long as 1 minute, timing out. But connectivity is not lost: pings to the same server from which I'm downloading works; one provider yields 20% packet loss, another 1% - so packet loss is probably not the main issue. YOU takes seemingly for ever. Ftp downloads are slow. Browsing of large pages is also slow. ** Tests done ** 1) Plug the modem on my old Pentium 120 machine, running SuSE 7.3, text only. Route through intranet (one ethernet cable, direct, 100 Mb/s). Change default route in main computer (SuSE 9.1) to eth0, and do the downloading, name solving, etc, on this "fast" machine - no software is changed at all - except that wvdial and pppd runs on the other 7.3 machine. +----------+ +-----------+ +------+ | P-120 | | P-IV 1.8Gh| ---phone---|modem |---rs232---| SuSE 7.3 |--eth--| SuSE 9.1 | line +------+ | | | (fetch) | +----------+ +-----------+ Run and time a single download of 738442 bytes. During this download no other Internet activity is running (no fetchmail, no browsing, no email sending). There is the local firewall (Susefirewall2) and a local dns server. No high load tasks are running (no updatedb, for example), only the xterms on which I see the logs and enter the commands. 2), 3) Plug the modem back on my P-IV machine running SuSE 9.1. Remove default route to eth0. Repeat the download, using two different providers, to make sure. Everything else is the same. ** Conclusion of the 3 tests, in brief ** When routed through the old computer running SuSE 7.3, throughput is 5.04 KB/s (on previous, non meticulous tests, I saw speed peeks up to 8Kb when downloading email - surely due to compression). When using the fast, Pentium IV machine, with SuSE 9.1, average speed is between 1 - 2 Kbytes per second! (even less, in fact). This is a disgrace :-// I see a lot of ppp "decompression error" in the kernel logs: Jul 23 21:22:39 nimrodel kernel: PPP: VJ decompression error I count 37 of them during test #2 (none during test #3) - compared with 560 during 4 months usage of SuSE 8.2 on this same machine. ** Wild non-educated guess ** The kernel is loosing ACK packets, so the servers waits. ** Detailed results ** *********** TEST #1: teleline - routed through P120, SuSE 7.3 ************** cer@nimrodel:~> date ; time wget --timeout=45 --waitretry=10 --continue "http://old.spamassassin.org/released/Mail-SpamAssassin-2.63.tar.bz2" Fri Jul 23 20:52:39 CEST 2004 - --20:52:39-- http://old.spamassassin.org/released/Mail-SpamAssassin-2.63.tar.bz2 => `Mail-SpamAssassin-2.63.tar.bz2' Resolving old.spamassassin.org... 64.142.3.173 Connecting to old.spamassassin.org[64.142.3.173]:80... connected. HTTP request sent, awaiting response... 200 OK Length: 738,442 [application/x-bzip2] 100%[==============================================================================>] 738,442 5.10K/s ETA 00:00 20:55:03 (5.04 KB/s) - `Mail-SpamAssassin-2.63.tar.bz2' saved [738442/738442] real 2m24.400s user 0m0.043s sys 0m0.065s cer@nimrodel:~> l Mail-SpamAssassin-2.63.tar.bz2 - -rw-r--r-- 1 cer users 738442 2004-01-20 23:06 Mail-SpamAssassin-2.63.tar.bz2 cer@nimrodel:~> rm Mail-SpamAssassin-2.63.tar.bz2 *********** TEST #2: teleline, direct, PIV - SuSE 9.1 ************** cer@nimrodel:~> date ; time wget --timeout=45 --waitretry=10 --continue "http://old.spamassassin.org/released/Mail-SpamAssassin-2.63.tar.bz2" Fri Jul 23 21:04:31 CEST 2004 - --21:04:31-- http://old.spamassassin.org/released/Mail-SpamAssassin-2.63.tar.bz2 => `Mail-SpamAssassin-2.63.tar.bz2' Resolving old.spamassassin.org... 64.142.3.173 Connecting to old.spamassassin.org[64.142.3.173]:80... connected. HTTP request sent, awaiting response... 200 OK Length: 738,442 [application/x-bzip2] 5% [==> ] 37,314 541.56B/s ETA 23:15 21:06:27 (541.46 B/s) - Read error at byte 37314/738442 (Connection timed out). Retrying. - --21:06:28-- http://old.spamassassin.org/released/Mail-SpamAssassin-2.63.tar.bz2 (try: 2) => `Mail-SpamAssassin-2.63.tar.bz2' Connecting to old.spamassassin.org[64.142.3.173]:80... connected. HTTP request sent, awaiting response... 200 OK Continued download failed on this file, which conflicts with `-c'. Refusing to truncate existing file `Mail-SpamAssassin-2.63.tar.bz2'. real 1m57.632s user 0m0.005s sys 0m0.008s So, I remove the "continue" and increase the timeout value, and try again. cer@nimrodel:~> date ; time wget --timeout=90 --waitretry=10 "http://old.spamassassin.org/released/Mail-SpamAssassin-2.63.tar.bz2" Fri Jul 23 21:08:13 CEST 2004 - --21:08:13-- http://old.spamassassin.org/released/Mail-SpamAssassin-2.63.tar.bz2 => `Mail-SpamAssassin-2.63.tar.bz2.2' Resolving old.spamassassin.org... 64.142.3.173 Connecting to old.spamassassin.org[64.142.3.173]:80... connected. HTTP request sent, awaiting response... 200 OK Length: 738,442 [application/x-bzip2] 10% [=======> ] 76,410 2.16K/s ETA 05:15 12% [=========> ] 95,234 601.24B/s ETA 10:52 22% [================> ] 166,186 694.98B/s ETA 10:40 29% [======================> ] 219,762 896.54B/s ETA 10:49 {xterm resize} 41% [=====================> ] 305,194 496.80B/s ETA 10:03 {xterm resize} 43% [================> ] 321,122 412.63B/s ETA 10:49 96% [======================================> ] 709,186 538.58B/s ETA 00:37 100%[========================================>] 738,442 2.21K/s ETA 00:00 21:23:27 (809.97 B/s) - `Mail-SpamAssassin-2.63.tar.bz2.2' saved [738442/738442] real 15m13.735s user 0m0.006s sys 0m0.016s Connectivity was not lost during pauses: cer@nimrodel:~> ping old.spamassassin.org PING bugzilla.spamassassin.org (64.142.3.173) 56(84) bytes of data. 64 bytes from bugzilla.spamassassin.org (64.142.3.173): icmp_seq=1 ttl=46 time=319 ms 64 bytes from bugzilla.spamassassin.org (64.142.3.173): icmp_seq=2 ttl=46 time=286 ms 64 bytes from bugzilla.spamassassin.org (64.142.3.173): icmp_seq=3 ttl=46 time=289 ms 64 bytes from bugzilla.spamassassin.org (64.142.3.173): icmp_seq=7 ttl=46 time=307 ms 64 bytes from bugzilla.spamassassin.org (64.142.3.173): icmp_seq=9 ttl=46 time=306 ms - --- bugzilla.spamassassin.org ping statistics --- 10 packets transmitted, 5 received, 50% packet loss, time 9003ms rtt min/avg/max/mdev = 286.976/302.200/319.884/12.398 ms cer@nimrodel:~> But you see a "50% packet loss" - although not always: cer@nimrodel:~> ping old.spamassassin.org PING bugzilla.spamassassin.org (64.142.3.173) 56(84) bytes of data. 64 bytes from bugzilla.spamassassin.org (64.142.3.173): icmp_seq=1 ttl=46 time=306 ms 64 bytes from bugzilla.spamassassin.org (64.142.3.173): icmp_seq=2 ttl=46 time=286 ms 64 bytes from bugzilla.spamassassin.org (64.142.3.173): icmp_seq=3 ttl=46 time=280 ms 64 bytes from bugzilla.spamassassin.org (64.142.3.173): icmp_seq=4 ttl=46 time=282 ms 64 bytes from bugzilla.spamassassin.org (64.142.3.173): icmp_seq=5 ttl=46 time=282 ms 64 bytes from bugzilla.spamassassin.org (64.142.3.173): icmp_seq=6 ttl=46 time=279 ms 64 bytes from bugzilla.spamassassin.org (64.142.3.173): icmp_seq=7 ttl=46 time=278 ms - --- bugzilla.spamassassin.org ping statistics --- 7 packets transmitted, 7 received, 0% packet loss, time 6005ms rtt min/avg/max/mdev = 278.978/285.684/306.956/9.035 ms cer@nimrodel:~> The round trip increases notably when the download resumes. I tend to leave a terminal pinging something continuously, else my wvdial session timeouts at 60" (local phone is charged by the minute here), so I do know the server from which I'm downloading is not down. cer@nimrodel:~> ping -a -A old.spamassassin.org PING bugzilla.spamassassin.org (64.142.3.173) 56(84) bytes of data. ... - --- bugzilla.spamassassin.org ping statistics --- 208 packets transmitted, 167 received, 19% packet loss, time 82875ms rtt min/avg/max/mdev = 277.933/412.677/1731.743/272.088 ms, pipe 4, ipg/ewma 400.366/677.842 ms *********** TEST #3: tiscali, direct, PIV - SuSE 9.1 ************** Test done using an alternate provider; everything else is the same as test number 2. cer@nimrodel:~> date ; time wget --timeout=90 --waitretry=10 "http://old.spamassassin.org/released/Mail-SpamAssassin-2.63.tar.bz2" Fri Jul 23 21:27:25 CEST 2004 - --21:27:25-- http://old.spamassassin.org/released/Mail-SpamAssassin-2.63.tar.bz2 => `Mail-SpamAssassin-2.63.tar.bz2.3' Resolving old.spamassassin.org... 64.142.3.173 Connecting to old.spamassassin.org[64.142.3.173]:80... connected. HTTP request sent, awaiting response... 200 OK Length: 738,442 [application/x-bzip2] 2% [ ] 15,609 1.27K/s ETA 12:10 86% [==================================> ] 636,801 1.59K/s ETA 01:05 100%[========================================>] 738,442 885.09B/s ETA 00:00 21:36:03 (1.40 KB/s) - `Mail-SpamAssassin-2.63.tar.bz2.3' saved [738442/738442] real 8m37.800s user 0m0.006s sys 0m0.008s Pings during this download: - --- bugzilla.spamassassin.org ping statistics --- 714 packets transmitted, 705 received, 1% packet loss, time 444595ms rtt min/avg/max/mdev = 298.668/650.054/4098.931/515.073 ms, pipe 7, ipg/ewma 623.555/301.994 ms - -- Cheers, Carlos Robinson -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.4 (GNU/Linux) Comment: Made with pgp4pine 1.76 iD8DBQFBAnkdtTMYHG2NR9URAr2VAJ9lYUrntn4LwO74A160NqRfTHmfRACfZoZ6 2Mza1LzuBsEZwy/ccQAGQvA= =C0UE -----END PGP SIGNATURE-----