Re: Linux Wireless USB-Stick Question

From: Larry Finger
Date: Wed Aug 03 2011 - 17:06:00 EST


On 08/03/2011 02:53 PM, Justin Piszcz wrote:
Hi,

Under Windows, you can achieve 10-15MiB/s..

Under Linux, even with 150mbps USB wireless adapters, the max never appears to
go above > 3-4MiB/s, to work around this, order more USB-wifi ticks and run them
in parallel far away from each other with USB
extenders:

box1:
-------------
wlan0 IEEE 802.11bg ESSID:"hidden"
Bit Rate=54 Mb/s Tx-Power=20 dBm
wlan1 IEEE 802.11bgn ESSID:"hidden"
Bit Rate=58.5 Mb/s Tx-Power=20 dBm
wlan2 IEEE 802.11bgn ESSID:"hidden"
Bit Rate=39 Mb/s Tx-Power=20 dBm

box2:
-------------
wlan0 IEEE 802.11bgn ESSID:"hidden"
Bit Rate=58.5 Mb/s Tx-Power=20 dBm
wlan1 IEEE 802.11bgn ESSID:"hidden"
Bit Rate=52 Mb/s Tx-Power=20 dBm
wlan2 IEEE 802.11bgn ESSID:"hidden"
Bit Rate=52 Mb/s Tx-Power=20 dBm

But I was curious if anyone had achieved > 10 MiB/s with any wireless adapter
with Linux?

Also, those native Linux USB adapters (carl) work good, so far.
With the patch provided earlier for the rt2800usb driver, it is no longer
crashing under 3.0 so I put two of them on a single box plus a carl based one,
now I get better I/O, e.g. 4MiB/s x 6 = 24MiB/s.

On a 150 Mbps connection running the following script

#!/bin/sh

dest="sonylap" # set the servername

while true ; do
netperf -t TCP_MAERTS -H $dest
netperf -t TCP_STREAM -H $dest
netperf -t TCP_SENDFILE -H $dest
done

I get the following for a D-Link DWA-130 containing a Realtek RTL8192SU with driver r8712u:

finger@larrylap:~/bcm_git/vendor-driver/5.10.56.46> ~/netperf.sh
TCP MAERTS TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to sonylap (192.168.1.50) port 0 AF_INET
Recv Send Send
Socket Socket Message Elapsed
Size Size Size Time Throughput
bytes bytes bytes secs. 10^6bits/sec

87380 16384 16384 10.04 53.52
TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to sonylap (192.168.1.50) port 0 AF_INET
Recv Send Send
Socket Socket Message Elapsed
Size Size Size Time Throughput
bytes bytes bytes secs. 10^6bits/sec

87380 16384 16384 10.03 55.58
TCP SENDFILE TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to sonylap (192.168.1.50) port 0 AF_INET
Recv Send Send
Socket Socket Message Elapsed
Size Size Size Time Throughput
bytes bytes bytes secs. 10^6bits/sec

87380 16384 16384 10.06 65.26

I claim that 50-65 Mbps is pretty good.

We get better than 10 Mbps with lots of different adapters.

Larry
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/