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Date: Tue, 29 May 2012 15:00:08 +0200
From: Tobias Diedrich <ranma+openwrt@tdiedrich.de>
To: Dave Taht <dave.taht@gmail.com>
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Subject: Re: [Codel] BQL support in Ethernet drivers (and Kathie Nichols and
 Van Jacobson's new AQM, codel)
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Dave Taht wrote:
> In looking over your test scripts and results, it seems possible you
> have gso on.

The driver didn't implement any advanced hardware features, so GSO
was unsupported.

Still, I've found the performance for this SoC is heavily limited by
memory bandwith and implementing scatter/gather support and hw
checksum offload improves TCP_STREAM performance greatly (About
doubled throughput).

Case in point, a second device with basically the same SoC, but slightly
faster (384MHz instead of 320MHz) and double the memory bandwith
(two chips instead of one) reaches twice the speed of the first
device (and also doubles the speed when scatter/gather and checksum
offload is enabled).

I haven't done any further testing with fq_codel yet.

-- 
Tobias						PGP: http://8ef7ddba.uguu.de