Re: 2.6.38: rt2800usb: high latency (1000ms)?

From: Marc Dietrich
Date: Wed Apr 13 2011 - 15:00:25 EST

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Hello Ivo,

Am Mittwoch 13 April 2011, um 17:59:07 schrieb Ivo Van Doorn:
> Hi,
>
> > I recall using this driver in staging and it crashing my machine, now
> > thats its no longer in staging, I thought I'd give it another try..
> > Using the
>
> The rt2800usb was not in staging but has been inside the main kernel
> tree for quite
> some time already, the alternative rt2870sta was in staging and will
> be removed very soon.
>
> > following wireless usb adapter, I'm seeing very high latency when using
> > the device in Linux, (with Windows, there are no problems). Using Debian
>
> > Testing + wpa_supplicant, using the following USB adapter:
> Can you try disabling powersaving?
> iwconfig wlan0 power off

this doesn't helps with the ping times here and it also doesn't prevent the
network traffic to stall from time to time (e.g. using apt-get install <some
package>).

Additionaly I found the following in the log:

[ 2701.455472] phy0 -> rt2x00usb_watchdog_tx_dma: Warning - TX queue 0 DMA timed
out, invoke forced forced reset
[ 2701.655222] phy0 -> rt2x00queue_flush_queue: Warning - Queue 0 failed to
flush
[ 2702.461590] phy0 -> rt2x00usb_watchdog_tx_dma: Warning - TX queue 0 DMA timed
out, invoke forced forced reset
[ 2702.655224] phy0 -> rt2x00queue_flush_queue: Warning - Queue 0 failed to
flush
[ 2703.455119] phy0 -> rt2x00usb_watchdog_tx_dma: Warning - TX queue 0 DMA timed
out, invoke forced forced reset
[ 2703.655072] phy0 -> rt2x00queue_flush_queue: Warning - Queue 0 failed to
flush
[ 2704.454070] phy0 -> rt2x00usb_watchdog_tx_dma: Warning - TX queue 0 DMA timed
out, invoke forced forced reset
[ 2704.645024] phy0 -> rt2x00queue_flush_queue: Warning - Queue 0 failed to
flush

This is with latest driver (rt2x00 master from today) backported to 2.6.37. The
machine is arm tegra and the chip is a rt3070. Output of ping with "power off":

marc@ac100:~$ sudo ping -i 0.01 -s 1400 192.168.10.1
PING 192.168.10.1 (192.168.10.1) 1400(1428) bytes of data.
1408 bytes from 192.168.10.1: icmp_req=1 ttl=64 time=10.9 ms
1408 bytes from 192.168.10.1: icmp_req=2 ttl=64 time=24.4 ms
1408 bytes from 192.168.10.1: icmp_req=3 ttl=64 time=6.72 ms
1408 bytes from 192.168.10.1: icmp_req=4 ttl=64 time=25.7 ms
1408 bytes from 192.168.10.1: icmp_req=5 ttl=64 time=7.01 ms
1408 bytes from 192.168.10.1: icmp_req=6 ttl=64 time=22.7 ms
1408 bytes from 192.168.10.1: icmp_req=7 ttl=64 time=9.07 ms
1408 bytes from 192.168.10.1: icmp_req=8 ttl=64 time=25.7 ms
1408 bytes from 192.168.10.1: icmp_req=9 ttl=64 time=6.07 ms

1408 bytes from 192.168.10.1: icmp_req=10 ttl=64 time=1931 ms
1408 bytes from 192.168.10.1: icmp_req=11 ttl=64 time=1920 ms
1408 bytes from 192.168.10.1: icmp_req=12 ttl=64 time=1917 ms
1408 bytes from 192.168.10.1: icmp_req=13 ttl=64 time=1897 ms
1408 bytes from 192.168.10.1: icmp_req=14 ttl=64 time=1878 ms
1408 bytes from 192.168.10.1: icmp_req=15 ttl=64 time=1858 ms

1408 bytes from 192.168.10.1: icmp_req=16 ttl=64 time=23.2 ms
1408 bytes from 192.168.10.1: icmp_req=17 ttl=64 time=11.6 ms
1408 bytes from 192.168.10.1: icmp_req=18 ttl=64 time=23.9 ms
1408 bytes from 192.168.10.1: icmp_req=19 ttl=64 time=7.26 ms
1408 bytes from 192.168.10.1: icmp_req=20 ttl=64 time=22.6 ms
1408 bytes from 192.168.10.1: icmp_req=21 ttl=64 time=4.46 ms
1408 bytes from 192.168.10.1: icmp_req=22 ttl=64 time=25.8 ms
1408 bytes from 192.168.10.1: icmp_req=23 ttl=64 time=10.6 ms
1408 bytes from 192.168.10.1: icmp_req=24 ttl=64 time=23.2 ms
1408 bytes from 192.168.10.1: icmp_req=25 ttl=64 time=4.15 ms
1408 bytes from 192.168.10.1: icmp_req=26 ttl=64 time=21.5 ms
1408 bytes from 192.168.10.1: icmp_req=27 ttl=64 time=6.64 ms
1408 bytes from 192.168.10.1: icmp_req=28 ttl=64 time=21.6 ms

1408 bytes from 192.168.10.1: icmp_req=29 ttl=64 time=1792 ms
1408 bytes from 192.168.10.1: icmp_req=30 ttl=64 time=1811 ms
1408 bytes from 192.168.10.1: icmp_req=31 ttl=64 time=1794 ms
1408 bytes from 192.168.10.1: icmp_req=32 ttl=64 time=1774 ms
1408 bytes from 192.168.10.1: icmp_req=33 ttl=64 time=1755 ms

1408 bytes from 192.168.10.1: icmp_req=34 ttl=64 time=23.4 ms
1408 bytes from 192.168.10.1: icmp_req=35 ttl=64 time=7.42 ms
1408 bytes from 192.168.10.1: icmp_req=36 ttl=64 time=26.1 ms
1408 bytes from 192.168.10.1: icmp_req=37 ttl=64 time=6.85 ms
1408 bytes from 192.168.10.1: icmp_req=38 ttl=64 time=21.9 ms
1408 bytes from 192.168.10.1: icmp_req=39 ttl=64 time=3.21 ms
1408 bytes from 192.168.10.1: icmp_req=40 ttl=64 time=22.5 ms
1408 bytes from 192.168.10.1: icmp_req=41 ttl=64 time=3.93 ms
1408 bytes from 192.168.10.1: icmp_req=42 ttl=64 time=24.3 ms
1408 bytes from 192.168.10.1: icmp_req=43 ttl=64 time=5.07 ms
1408 bytes from 192.168.10.1: icmp_req=44 ttl=64 time=21.8 ms
1408 bytes from 192.168.10.1: icmp_req=45 ttl=64 time=7.76 ms

1408 bytes from 192.168.10.1: icmp_req=46 ttl=64 time=1974 ms
1408 bytes from 192.168.10.1: icmp_req=47 ttl=64 time=1965 ms
1408 bytes from 192.168.10.1: icmp_req=48 ttl=64 time=1976 ms
1408 bytes from 192.168.10.1: icmp_req=49 ttl=64 time=1957 ms
1408 bytes from 192.168.10.1: icmp_req=50 ttl=64 time=1942 ms
1408 bytes from 192.168.10.1: icmp_req=51 ttl=64 time=1923 ms

1408 bytes from 192.168.10.1: icmp_req=52 ttl=64 time=42.9 ms
1408 bytes from 192.168.10.1: icmp_req=53 ttl=64 time=27.1 ms
1408 bytes from 192.168.10.1: icmp_req=54 ttl=64 time=14.0 ms
1408 bytes from 192.168.10.1: icmp_req=55 ttl=64 time=21.2 ms
1408 bytes from 192.168.10.1: icmp_req=56 ttl=64 time=5.41 ms
1408 bytes from 192.168.10.1: icmp_req=57 ttl=64 time=22.1 ms
1408 bytes from 192.168.10.1: icmp_req=58 ttl=64 time=32.3 ms
1408 bytes from 192.168.10.1: icmp_req=59 ttl=64 time=19.2 ms
1408 bytes from 192.168.10.1: icmp_req=60 ttl=64 time=4.30 ms
1408 bytes from 192.168.10.1: icmp_req=61 ttl=64 time=25.7 ms
1408 bytes from 192.168.10.1: icmp_req=62 ttl=64 time=5.91 ms
1408 bytes from 192.168.10.1: icmp_req=63 ttl=64 time=21.7 ms
1408 bytes from 192.168.10.1: icmp_req=64 ttl=64 time=6.75 ms
^C
--- 192.168.10.1 ping statistics ---
70 packets transmitted, 64 received, 8% packet loss, time 6668ms
rtt min/avg/max/mdev = 3.212/513.169/1976.893/826.940 ms, pipe 7

You can see a clear pattern within the ping times.

Hope this helps,

Marc

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Next message: Iztasi: "Ncf Exrzoa"
Previous message: Tejun Heo: "Re: [patch v2 2/4] percpu_counter: delete dead code"
In reply to: Walter Goldens: "Re: 2.6.38: rt2800usb: high latency (1000ms)?"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]