hehe, another question.
I'm using Wireshark to see what's in flight. Whatever packet I choose to
write in the stack, I get packets of size 1460bytes maximum on the wire.

...
1902 6.432931 192.168.0.72 192.168.0.68 TCP 1008 > lanyon-lantern [ACK]
Seq=1709449 Ack=49 Win=17968 Len=1460
1904 6.434920 192.168.0.72 192.168.0.68 TCP 1008 > lanyon-lantern [ACK]
Seq=1710909 Ack=49 Win=17968 Len=1460
...

Having configured a MSS size of 9216, I was thinking I would see that as the
maximum. Why is it topped at 1460?

Oh an for the record (previous questions), I'm on a AVR32, having only 1
connection at any time and my streaming is AVR32--->PC all the time. The
communication PC--->AVR32 is only keep-alive packets and small requests from
time to time.



On Tue, Mar 30, 2010 at 3:31 PM, Dany Thiffeault <[email protected]>wrote:

> oh and Simon, another question. I haven't seen anything about this in your
> wiki, but are PBUF_POOL_SIZE and PBUF_POOL_BUFSIZE important too?
> I'm trying to put everything as high as possible, but I have linking
> problems because I need to much memory. Could you give me some suggestions
> on the parameters to choose if I want to send packets of 8k size, or more,
> something like this...
>
> #define MEM_SIZE                      10 * 1024
> #define MEMP_NUM_PBUF         16
> #define PBUF_POOL_SIZE          10
> #define PBUF_POOL_BUFSIZE    LWIP_MEM_ALIGN_SIZE(TCP_MSS+40+PBUF_LINK_HLEN)
> #define TCP_MSS                        9216
> #define TCP_WND                       (TCP_MSS * 2)
> #define TCP_SND_BUF                TCP_WND
> #define TCP_SND_QUEUELEN     6 * TCP_SND_BUF/TCP_MSS
>
> Best regards,
> Dany
>
>
> On Tue, Mar 30, 2010 at 12:01 PM, Dany Thiffeault <[email protected]
> > wrote:
>
>> Ok, I'm now back up-and-running. With Studio 2.5, Framework 1.7 and LWIP
>> 1.3.2. My streaming is working great at the moment. I'm limited to
>> 2.1Mbits/s of throughput though, so I started reading your Wiki page Simon
>> and trying things.
>>
>> I have one question:
>> - How do I know if the checksum can be calculated by the hardware? I'm
>> using a board I made but based on the Atmel EVK1100.
>>
>> Thanks!!!!
>> Dany
>>
>>
>> On Tue, Mar 23, 2010 at 11:50 AM, Martin Persich <[email protected]>wrote:
>>
>>>  Hi Dany,
>>> I'm workin with AVR32 too and I have similar problem in this momen (I
>>> have LwIP 1.3.2 + some CVS changes and Atmel framework 1.7 of course). My
>>> app is hanging with huge ethernet load (traffic approx 20 GB / day) sometime
>>> - once per day, but most often once per week, ... terrible situation. I am
>>> suspecting Atmel "macb.c" driver in this moment, I am not sure if all code
>>> in "macb.c" (function lMACBSend) is thread and IRQ safety. But it is only my
>>> last idea. I changed ETHERNET_CONF_NB_TX_BUFFERS from 10 to 24 two days
>>> ago ...
>>> I haven't any problem solution in this moment.
>>> Martin Persich
>>>
>>>
>>> ----- Original Message -----
>>> *From:* Dany Thiffeault <[email protected]>
>>> *To:* Mailing list for lwIP users <[email protected]>
>>> *Sent:* Monday, March 22, 2010 10:13 PM
>>> *Subject:* Re: [lwip-users] Help in getting maximum throughput with
>>> LWIP.
>>>
>>> wow, great thanks. I'll make some tests tomorrow.
>>>
>>> Indeed, I forgot to mention. I'm using TCP with the netconn API. While
>>> reading through the multiple posts I missed the past few months, I found out
>>> that 1.3.2 is out and Atmel framework 1.7 too. I'll upgrade everything
>>> tomorow.
>>>
>>> But in the meantime, I'm experiencing problems like I wrote. I don't know
>>> why my app is hanging in the tcp_in.c file. If somebody knows what's going
>>> on on that line, let me know.
>>>
>>>
>>>
>>> On Mon, Mar 22, 2010 at 5:05 PM, [email protected] <[email protected]>wrote:
>>>
>>>> I just took the time to write something about performance/throughput on
>>>> the wiki:
>>>> - http://lwip.wikia.com/wiki/Maximizing_throughput
>>>> - http://lwip.wikia.com/wiki/Tuning_TCP
>>>>
>>>> However, you didn't tell us if you are using TCP or UDP? Also, I don't
>>>> know what ETHERNET_CONF_NB_TX_BUFFERS is, so I'm guessing it's related to
>>>> the lwIP port you are using... Maybe someone else here has experience with
>>>> the platform you are using, but I don't :-(
>>>>
>>>> Simon
>>>>
>>>>
>>>> Dany Thiffeault wrote:
>>>>
>>>>  Hi,
>>>>
>>>> I'm currently coding an application on a AVR32 UC3 board. The board is
>>>> actually an acquisition platform that's using Ethernet (lwip 1.3.1
>>>> currently). I'm using FreeRTOS and the Atmel framework 1.4.
>>>>
>>>> My connection is working great with my Windows application. There are
>>>> two modes to my AVR32 application:
>>>>
>>>> 1- Idle mode where there are only keep-alive packets every 1 second, of
>>>> 8bytes each.
>>>> 2- Streaming mode, where the AVR32 (so LWIP) send data as fast as
>>>> possible to the Win application.
>>>>
>>>> What is important to me is to get maximum speed in Streaming mode, where
>>>> packets are Header(24bytes) + Data(?Bytes). I'm currently playing with the
>>>> data size to see what I can achieve. Ideally, the maximum size I would like
>>>> is about 35KBytes. Right now, I'm not sure what's going on, but the 
>>>> Ethernet
>>>> seems to hang after a few seconds of streaming. Haven't found the problem 
>>>> so
>>>> far.
>>>>
>>>> So, what are the important parameters for maximum thoughput in the
>>>> lwipopts.h file dans other #defines like ETHERNET_CONF_NB_TX_BUFFERS, etc.
>>>> I'm kind of lost in all those parameters.
>>>>
>>>> Thanks a lot!!
>>>> Dany
>>>>
>>>>
>>>> _______________________________________________
>>>> lwip-users mailing 
>>>> [email protected]http://lists.nongnu.org/mailman/listinfo/lwip-users
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> lwip-users mailing list
>>>> [email protected]
>>>> http://lists.nongnu.org/mailman/listinfo/lwip-users
>>>>
>>>
>>>
>>> _______________________________________________
>>> lwip-users mailing list
>>> [email protected]
>>> http://lists.nongnu.org/mailman/listinfo/lwip-users
>>>
>>
>>
>
_______________________________________________
lwip-users mailing list
[email protected]
http://lists.nongnu.org/mailman/listinfo/lwip-users

Reply via email to