rt2500pci wifi driver and slow SSH connection

[Mark Bennett]

IBM Thinkpad T23 with Comtrend PCMCIA wifi adapter. Wifi adapter purchased from Linux Emporium (Solihull, UK) and certified as Linux compatible, which so far is correct. Wifi adapter immediately recognised by Laptop and immediately connects to wifi DHCP router. Package installation via Synaptic and Update Manager very quick. Likewise web surfing very quick. The card is reported in lspci as follows:

03:00.0 Network controller: RaLink RT2500 802.11g Cardbus/mini-PCI (rev 01)

iwconfig reports:

wlan0 IEEE 802.11bg ESSID:"BTHomeHub-E2AF"
          Mode:Managed Frequency:2.462 GHz Access Point: 00:14:7F:9B:F3:F7
          Bit Rate=54 Mb/s Tx-Power=18 dBm
          Retry min limit:7 RTS thr:off Fragment thr=2352 B
          Power Management:off
          Link Quality=73/100 Signal level:-40 dBm
          Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
          Tx excessive retries:0 Invalid misc:0 Missed beacon:0

Network Manager>Connection Information reports:

Auto BTHomeHub-E2AF (default)
Interface: 802.11 Wifi (wlan0)
Hardware Address: 00:0F:EA:ED:D3:64
Driver: rt2500pci
Speed: 1Mb/s
Security: WEP
IP Address: 192.168.67
Broadcast Address: 192.168.1.255
Subnet Mask: 255.255.255.0
Default Route: 192.168.1.254
Primary DNS: 192.168.1.254

Problem:- Connection via openssh either as client or server machine is very slow. Transfer of files lasts for about 10 seconds at 500kb/s but then rapidly slows to 60kb/s resulting in anticipated file transfer of 1.2GB of data to take 19 hours. Left laptop overnight but in the morning the transfer across SSH had failed. Tried the laptop connected to 2 different Ubu machines. One running 8.04 and connected to router via ethernet cable. The other wifi connected running 9.04. The laptop has the same deceleration issue regardless of which machine it's trying to SSH with. The other machines in the network (both Ubu) transfer at 4MB/s across SSH with each other. One has an internal Belkin PCI wifi card (purchased from same vendor). The other is connected via ethernet cable. Transfer rates between these two other machines are fast and constant. The issue appears to be the laptop and I would guess the wifi driver having a problem with SSH. To test the laptop I've removed the wifi card and connected an ethernet cable. With this configuration SSH speeds of constant 3.8MB/s achieved and files successfully transferred. I can only conclude that the wifi driver is somehow losing packets resulting in the rapid deceleration and then settling to the very slow 60Kb/s transfer speed?

To double check the above issue I have done a complete fresh install of 9.04 onto the laptop and installed all the updates via Update Manager. The SSH transfer issue is repeated.

ProblemType: Bug
Architecture: i386
DistroRelease: Ubuntu 9.04
Package: ssh 1:5.1p1-5ubuntu1
PackageArchitecture: all
ProcEnviron:
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
SourcePackage: openssh
Uname: Linux 2.6.28-15-generic i686

[Brian Murray (brian-murray)]

Thanks for taking the time to report this bug and helping to make Ubuntu better. Please include you '/var/log/dmesg' file from the laptop after trying the file transfer for a while. Thanks in advance!

[Chuck Short (zulcss)]

We'd like to figure out what's causing this bug for you, but we haven't heard back from you in a while. Could you please provide the requested information? Thanks!

[burkaygenc (burkaygenc)]

I think I may help with this bug, because I have a similar problem. Let me first explain my case:

I have a desktop machine, which uses an rt2500pci driver. I have been using this wireless card since hardy. 9.10 is the first version to give me this problem.

Unlike the original poster, my problem is not limited to SSH. All connections to the Internet are limited to 60kb/s. Technically, I am on a 4mbit/s connection. So, my theoretical upper bound is about 475kb/s. It is not like I have low signal or any interference. It is just that Ubuntu refuses to do faster transfers. It is as if something is limiting my connection speed.

iwconfig gives the following:

[code]
wlan0 IEEE 802.11bg ESSID:"Burkay"
          Mode:Managed Frequency:2.437 GHz Access Point: 00:12:BF:67:8C:75
          Bit Rate=54 Mb/s Tx-Power=20 dBm
          Retry long limit:7 RTS thr:off Fragment thr:off
          Power Management:on
          Link Quality=41/70 Signal level=-69 dBm
          Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
          Tx excessive retries:0 Invalid misc:0 Missed beacon:0
[/code]

I know that ın earlier versions of ubuntu, txpower was set to 27dBm. Now it is set to 20 and I cannot change it to anything higher. Turning off power management does not help.

/var/log/dmesg is also below:

[code]bgenc@desktop-ubuntu:~$ cat /var/log/dmesg
[ 0.000000] Initializing cgroup subsys cpuset
[ 0.000000] Initializing cgroup subsys cpu
[ 0.000000] Linux version 2.6.31-14-generic-pae (buildd@rothera) (gcc version 4.4.1 (Ubuntu 4.4.1-4ubuntu8) ) #48-Ubuntu SMP Fri Oct 16 15:22:42 UTC 2009 (Ubuntu 2.6.31-14.48-generic-pae)
[ 0.000000] KERNEL supported cpus:
[ 0.000000] Intel GenuineIntel
[ 0.000000] AMD AuthenticAMD
[ 0.000000] NSC Geode by NSC
[ 0.000000] Cyrix CyrixInstead
[ 0.000000] Centaur CentaurHauls
[ 0.000000] Transmeta GenuineTMx86
[ 0.000000] Transmeta TransmetaCPU
[ 0.000000] UMC UMC UMC UMC
[ 0.000000] BIOS-provided physical RAM map:
[ 0.000000] BIOS-e820: 0000000000000000 - 000000000009f400 (usable)
[ 0.000000] BIOS-e820: 000000000009f400 - 00000000000a0000 (reserved)
[ 0.000000] BIOS-e820: 00000000000e6000 - 0000000000100000 (reserved)
[ 0.000000] BIOS-e820: 0000000000100000 - 00000000cffb0000 (usable)
[ 0.000000] BIOS-e820: 00000000cffb0000 - 00000000cffbe000 (ACPI data)
[ 0.000000] BIOS-e820: 00000000cffbe000 - 00000000cffe0000 (ACPI NVS)
[ 0.000000] BIOS-e820: 00000000cffe0000 - 00000000cffee000 (reserved)
[ 0.000000] BIOS-e820: 00000000cfff0000 - 00000000d0000000 (reserved)
[ 0.000000] BIOS-e820: 00000000e0000000 - 00000000f0000000 (reserved)
[ 0.000000] BIOS-e820: 00000000ff700000 - 0000000100000000 (reserved)
[ 0.000000] BIOS-e820: 0000000100000000 - 0000000128000000 (usable)
[ 0.000000] DMI present.
[ 0.000000] AMI BIOS detected: BIOS may corrupt low RAM, working around it.
[ 0.000000] e820 update range: 0000000000000000 - 0000000000010000 (usable) ==> (reserved)
[ 0.000000] last_pfn = 0x128000 max_arch_pfn = 0x1000000
[ 0.000000] MTRR default type: uncachable
[ 0.000000] MTRR fixed ranges ...

[Chuck Short (zulcss)]

I think this might be a bug in the driver.

Regards
chuck

[Rafael Gálvez-Cañero (galvesband)]

I'm affected by the issue described in #4. Should we open a new bug report or mark this as new/confirmed/whatever-makes-sense?

[Jeremy Foshee (jeremyfoshee)]

This bug report was marked as Incomplete and has not had any updated comments for quite some time. As a result this bug is being closed. Please reopen if this is still an issue in the current Ubuntu release http://www.ubuntu.com/getubuntu/download . Also, please be sure to provide any requested information that may have been missing. To reopen the bug, click on the current status under the Status column and change the status back to "New". Thanks.

[This is an automated message. Apologies if it has reached you inappropriately; please just reply to this message indicating so.]