Wireless DL very slow (Ralink RT2860/Realtek RTL8111)

[chili555]

I really wish you're still listening cause I tried your suggestion but the problem is still there.

Who, me? Like the other doctor says, "I'm listening."

I wanted to try this but I wasn't capable:
http://ubuntuforums.org/showpost.php...8&postcount=27

I got the following error:

Code:

dude@home:~$ uname -a
Linux NAS 2.6.35-30-generic-pae #60-Ubuntu SMP Mon Sep 19 22:29:36 UTC 2011 i686 GNU/Linux
dude@home:~$ sudo apt-get install linux-backports-modules-compat-wireless-2.6.38-lucid-generic meta-package
Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Unable to locate package linux-backports-modules-compat-wireless-2.6.38-lucid-generic
E: Couldn't find any package by regex 'linux-backports-modules-compat-wireless-2.6.38-lucid-generic'
E: Unable to locate package meta-package

But then:

I'm using Ubuntu 10.10 (Maverick Meerkat)

Before we explore that, let's discuss a few things. The trouble with using scp between your laptop and your server is that you don't know whether it's a flaw in the server or a flaw in the laptop. There are many areas to consider, too. Not just Samba but the webserver software on the server (LAMP??). Do you need Samba if the server is also Linux? I don't think so.

Is networking to the outside world good or slow on the laptop? Can you wget at a known good server at or close to your ISPs limit?

Have you reliably isolated the rt2860sta as the bottleneck?

[alfonso78]

Who, me? Like the other doctor says, "I'm listening."

Glad to hear that!

But then:Before we explore that, let's discuss a few things. The trouble with using scp between your laptop and your server is that you don't know whether it's a flaw in the server or a flaw in the laptop. There are many areas to consider, too. Not just Samba but the webserver software on the server (LAMP??). Do you need Samba if the server is also Linux? I don't think so.

Is networking to the outside world good or slow on the laptop? Can you wget at a known good server at or close to your ISPs limit?

Have you reliably isolated the rt2860sta as the bottleneck?

Let me state a few things:
- laptop is Windows XP
- server is the Ubuntu box

From the server I'm downloading this file (I live in France) ftp://ftp.free.fr/mirrors/ftp.ubuntu...-dvd-amd64.iso and I get only 156 KB/sec with wget.

As I was looking for an other huge file (to test a different server) the download spiked to 1 MB/sec and more and now it's around 700K (I never got this speed between the two PCs).

So, at the very least, the Ubuntu box offers very unstable performances (now at 700 KB/sec).

I stopped the 1st and tried downloading this: http://debian.mines.inpl-nancy.fr/de...desktop.tar.gz and I'm getting around 700KB/sec, sometimes close to 600, sometimes 800. Now more than 1MB. Now 600 KB/sec. A few secs later it shows 1.4MB/sec.

Is this fluctuation expected?

Just as a bonus experiment, I tried to download other two files from the same two servers using the ubuntu 10.04 I have running in VMWare in my XP laptop and I saw similar fluctuations from 200K to 1MB/sec (which doesn't help me prove anything...)

Dear doctor, I'll sleep now. I hope maybe tomorrow I can do some more tests and get to the bottom of it. Wireless performance is key to this project. Over the weekend I was planning to try 11.10 (to get latest drivers etc).

thank you!

[chili555]

Sleep well. See you tomorrow.

I just tried the latter download and my speeds are also all over the place. Here are random readings from wget in Kb/s.

317
205
283
342
199
275
85
193
328
232
271
83
232

I believe that reflects the server speed and not my Ubuntu Linux machines speed. I downloaded a big pdf a few minutes ago that stayed in the 340 to 350 Kb/s range throughout.

[alfonso78]

I downloaded a big pdf a few minutes ago that stayed in the 340 to 350 Kb/s range throughout.

Thank you for helping!

So what should I expect as W-LAN internal transfer rate then?

Even a 1MB steady stream would be better than this. Bother laptop and server can reach such speed.

Both server and laptop can be hooked up to the router via cable, so I'll test all four possibilities hoping this will give me some additional insight over where is the problem.

see you tomorrow!

[alfonso78]

So, here we are, a lot of data points! Hopefully some sense can come out of them.

First of all I changed my WiFi router (it required a reset every now and then and I had it since 3 years, so I thought it was a good idea anyway).

Yesterday I tested my dsl from both XP and Ubuntu over WiFi and I remember they were pretty comparable around 10-11Mbit/sec (maybe I remember wrong).

Results today (using speedtest.net):

wireless XP: 32ms (ping), 12.43 Mbit downstream, 0.74 Mbit upstream
wired XP: 32ms (ping), 12.12 Mbit downstream, 0.74 Mbit upstream
wireless Ubuntu: 17ms (ping), 7.61 Mbit downstream, 0.78 Mbit upstream
wired Ubuntu: 17ms (ping), 12.60 Mbit downstream, 0.78 Mbit upstream

Would you agree these results alone indicate a problem on the wireless connectivity in Ubuntu?

I wanted to share these results. Now I will also test file transfer between the two when one of the two PCs is wired and when both are wired.

thank you!

[alfonso78]

By the way, I was also thinking to try to look for the least polluted wifi channel (how?) but given the wireless XP results, I don't think it's a priority in order to solve this problem!

[alfonso78]

So here are the test results using SCP (simply because winSCP shows the speed).
Test conditions: copying a 2GB file over SCP and watching at least 30 secs to see if the speed changes.


wired XP and wired ubuntu: peaks of 2,700 KB/sec but never below 2,200 KB/sec - a few secs it showed 1,500 KB/sec but then went back quickly to 2,500 KB/sec
wireless XP and wired ubuntu: peaks of 1,300 KB/sec but never below 1100 KB/sec
wired XP and wireless ubuntu: peaks of 800 KB/sec then stays in the 300-400KB/sec range, then up to 800 again, then 600, then 400. It stays a bit at 400, then 600. It's really unstable.

Now I'm not sure what else to do (except praying for a miracle with the 11.10 drivers). If you have any test or suggestion, feel free!!!

Thank you!

[phil338198]

Hello!
The original problem of this thread appeared again in oneiric.
I no longer have rt2860sta so right after the upgrade, my wifi did not work.
I removed the blacklisting of rt2800pci and my wifi worked again, but there is still some speed variations.

With rt2800sta, I had 54Mb/s all the time, now with rt2800pci, I'm usually at 45Mb/s but it varies between 10Mb/s ant 135Mb/s...

lsmod | grep rt2 gives me:

rt2800pci              18715  0 
rt2800lib              54306  1 rt2800pci
crc_ccitt              12667  1 rt2800lib
rt2x00pci              14578  1 rt2800pci
rt2x00lib              50325  3 rt2800pci,rt2800lib,rt2x00pci
mac80211              310872  3 rt2800lib,rt2x00pci,rt2x00lib
cfg80211              199587  2 rt2x00lib,mac80211
eeprom_93cx6           12725  1 rt2800pci

Any help is welcome! If i could get my card to a steady 135Mb/s it would be great.

[alfonso78]

Apologies for overlapping...

I noticed an other thing. In /var/log/messages there is a similar message posted every 2 minutes:

Oct 14 13:15:15 NAS kernel: [137913.398670] ===>rt_ioctl_giwscan. 36(36) BSS returned, data->length = 4658

and on this page this error message is connected to rt2860:
https://bugs.launchpad.net/ubuntu/+s...ux/+bug/356807

[alfonso78]

So, now I'm also on 11.10 and scp throughput fluctuates between 200 and 600 K/sec

I also tried to blacklist rt2800pci in /etc/modprobe.d/blacklist.conf and add rt2860sta in /etc/modules but somehow it doesn't get loaded at startup.

if you're still out there, any help would be greatly appreciated!

also FYI and for my memory, I found this article which I followed:
http://michael-peeters.blogspot.com/...er-ubuntu.html

but apparently (did I do something wrong?) there is no difference between the rt2860sta I manually compiled and the one found in /lib/modules/3.0.0-12-generic-pae/kernel/drivers/net/wireless/

they are binary identical.

But I can't test much if I can't load it.