Re: ppc405ex + gigabit ethernet

[Lada Podivin <lada.podivin@gmail.com>]

[-- Attachment #1: Type: text/plain, Size: 2337 bytes --]

Eh! I mean Mb/s NOT Kb/s! Sorry!

2009/7/1 Lada Podivin <lada.podivin@gmail.com>

> Thank you for your reply!
> Yes, I agree the CPU is the bottleneck. But I have performed more tests
> with the netperf tool and results seem strange to me. If I send 800 B of
> data, the resulting speed is aproximately 100 Kb/s. On the other hand, If I
> try to send 32KB chunk of data with jumbo frames turned on, resulting speed
> is about 600 Kb/s (300-400 without jumbo frames). My ppc405ex runs at 600
> MHz.
>
> So it seems that it is definetely better idea to call sendto() less
> frequently with bigger amounts of data, than to call it more often with
> smaler amounts. Is it because smaller data means more frequent user
> space/kernel space switching? Or is it network related issue?
>
> Thanks!
>
> Best,
> Lada
>
> 2009/7/1 LiuMing <eemingliu@hotmail.com>
>
>  Hi,
>> According to our experience on PPC405 + Gigabit Enet, your result is
>> already very reasonable. For UDP transmission, it can be around 400 Kb/s
>> because of the CPU bottleneck (in our case 300 MHz ppc405). If you want
>> to further improve it, a faster CPU is needed to process the TCP/IP stack,
>> or you may buy commercial TCP/IP stack rather than using the free Linux one.
>>
>>
>> BR
>> Ming
>>
>> ------------------------------
>> Date: Tue, 30 Jun 2009 15:58:53 +0200
>> Subject: ppc405ex + gigabit ethernet
>> From: lada.podivin@gmail.com
>> To: linuxppc-dev@ozlabs.org
>>
>>
>> Hi,
>>
>> I benchmarked performance of my network, which contains ppc405EX (Kilauea
>> board, kernel 2.6.30 from Denx) connected with a linux desktop via gigabit
>> ethernet. I used the netperf tool:
>>
>> netperf -t UDP_STREAM -H 192.168.1.1 -- -m 32768
>>
>> So I was sending UDP packets to the desktop. The resulting speed was about
>> 370 Kb/s. I tried to send the packets to several different computers - with
>> the same result. So the ppc board is the bottleneck in this case.
>>
>> Is there any possibility to improve the gigabit capabilities of the
>> ppc405EX? Is there anyone who achieved a better performance with ppc4xx
>> boards?
>>
>> Thanks!
>>
>> Best,
>> Lada Podivin
>>
>>
>> ------------------------------
>> 立刻下载 MSN 保护盾，保障 MSN 安全稳定！ 现在就下载！ <http://im.live.cn/safe/>
>>
>
>

[-- Attachment #2: Type: text/html, Size: 3043 bytes --]