RTL-8139 Network card slow down on 2.6.8.1-mm

RTL-8139 Network card slow down on 2.6.8.1-mm

[Unai Garro]

Hi, it seems the last mm patches for 2.6.8.1 have caused my network card 
(Realtek 8139)  to go buggy. 

When downloading big files (say ftp.kernel.org last kernel) the card will 
begin downloading at fullspeed of my adsl line, but it will start slowing 
down the speed, down to zero.

I can't see this effect on the vanilla 2.6.8.1 kernel, but it seems to happen 
on both -mm3 & -mm4 that I tested. I'm not using any traffic shaping and I 
even tried to disable quite a few network features trying to solve it with no 
good results.

I wish I could provide more info than this, but dmesg doesn't seem to show any 
problems, and I really don't know how to provide more useful data on this. 
Please let me know if I can help with debugging this or providing more data 
somehow

 Unai

PS: Sorry for writing to this list being it -mm specific, but the linux-mm 
list address that I have doesn't seem to work anymore

Re: RTL-8139 Network card slow down on 2.6.8.1-mm

[Francois Romieu]

Unai Garro <ugarro@telefonica.net> :
> Hi, it seems the last mm patches for 2.6.8.1 have caused my network card 
> (Realtek 8139)  to go buggy. 

*blush*

This should fix it:

http://www.fr.zoreil.com/linux/kernel/2.6.x/2.6.8-rc4-mm1/8139too-mm-revert.patch
http://www.fr.zoreil.com/linux/kernel/2.6.x/2.6.8-rc4-mm1/8139too-10.patch
http://www.fr.zoreil.com/linux/kernel/2.6.x/2.6.8-rc4-mm1/8139too-20.patch

--
Ueimor

Re: RTL-8139 Network card slow down on 2.6.8.1-mm

[Unai Garro]

Francois Romieu wrote:
> This should fix it:
> 
> 
http://www.fr.zoreil.com/linux/kernel/2.6.x/2.6.8-rc4-mm1/8139too-mm-revert.patch
> http://www.fr.zoreil.com/linux/kernel/2.6.x/2.6.8-rc4-mm1/8139too-10.patch
> http://www.fr.zoreil.com/linux/kernel/2.6.x/2.6.8-rc4-mm1/8139too-20.patch

Yes, that seems to work just fine now. Thanks for the quick response

 Unai

Re: RTL-8139 Network card slow down on 2.6.8.1-mm

[dag]

Hi Francois, Jeff

I have noticed an anomaly with the 8139C network card which I would like
to hear your opinion about, if you have time to spare.
I don't think it is the same problem which started this thread.

I have been testing a specific kind of networking equipment with two
laptops equipped with RTL8139C cardbus cards. 
I use the application 'iperf' to measure troughput.
To establish the base level bandwidth, I use a crossover cable between
the two PCs, and measure the bandwidth "back to back".

With UDP, I easily achieve around 93-94 Mbps with these cards, be it
one-way or two-way traffic.

With TCP, I achieve 92-93 Mbps with one-way traffic. Two-way traffic is
variable, and my main question revolves around this fact.

I have on one, single occation been able to measure 90 Mbps two-way TCP
traffic. More common is 86-87 Mbps. Occasionally, two-way traffic drops
down to 67 Mbps. The only way to get it back up is to pull the cards and
put them back in.

If there had been packet drops (I need to generate stats here...) I'd
understand it if the TCP protocol was throttling the troughput. But I am
not convinced that is the issue here.


- What troughput (2way, TCP) should I be able to achieve with the
RTL8139C and the 8139too driver?

- Does the hardware support flow control?

- Is there a particular reason the NAPI patch for the 8139 isn't merged
yet?

I am currently testing with 2.6.8.1 + the 8139 napi patch + the two 8139
patches in -mm1.


Regards,


Dag B.