[ewg] Re: [ofa-general] [PATCH] IB/ipoib: fix net queue lockup

[Eli Cohen]

On Thu, 2008-05-01 at 08:07 -0700, Roland Dreier wrote:

> OK, that makes sense -- although did you see any performance difference?
Yes. With four streams on a 4 cores machine, the senders sum up to:
898 * 10^6 bits/sec  @ 256 tx queue length
756 * 10^6 bits/sec  @ 64 tx queue length

> 
>  > Also looking for example on Broadcom bnx2 driver on my machine, it uses
>  > a 1000 tx queue len.
> 
> Isn't that the software queue above the hardware?  (That's what
> txqueuelen in ifconfig is reporting)
I wrongly assumed this is the hardware queue size. Now I looked at the
driver code and if I did not make any mistake in the calculations, the
hardware queue size is... 256.