Subject: Re: Using ethernet device as efficient small packet generator

From: Ben Greear <[email-masked]>
Date: Fri, 21 Jan 2011 05:38:34 -0800

On 01/21/2011 04:12 AM, juice wrote:
>> Le vendredi 21 janvier 2011 Ã  13:44 +0200, juice a Ã©crit :
>>
>>
>> You should try
>>
>> CLONE_SKB="clone_skb 10"
>> ...
>> pgset "$CLONE_SKB"
>>
>>
>> Because I suspect you hit a performance problem on skb
>> allocation/filling/use/freeing
>
> Actually, that makes the performance worse:
> (Now I tried it with kernel 2.6.37, which is currently running)

Maybe try clone-skb of 1000 or so.  It zero's it's memory when
allocating a packet which can be quite expensive.

Also note that the Ethernet inter-frame gap isn't accounted for in
the BPS, but it is a significant amount of the total bandwidth
when using 64-byte packets.
You are pushing a bit more than half of the theoretical limit of
around 1,400,000 64-byte packets per second for 1Gbps ethernet.

Thanks,
Ben

-- 
Ben Greear <[email-masked]>
Candela Technologies Inc  http://www.candelatech.com