Hi All,
Recently I have been trying to upgrade to lwip140 from lwip130.
Below are my observations.
If I do not change anything (same hardware, same parameters in opt.h and same application files), then Rx side lwip140 performance is better than lwip130, but on the Tx side the performance it is the opposite. lwip130 is better.
So no issues on receive side. But some on the Tx side.
I went through the "tcp_write" code and compared it with older "tcp_write". There is a huge change in implementation.
Then I changed my application so that when I call tcp_write, I pass the 4th argument (COPY) as zero. So I am telling the stack to use the same buffer and do not copy it to local buffer. With it my performance improved many folds. Just to give you an idea, with my change it is around 128 Mbps and without this, it was 86. So the new tcp_write interface is designed in such a way that if I ask it not to copy, then it behaves great.
Same thing does not apply for lwip130. For lwip130, if I pass the 4th argument to tcp_write as 0, the improvement is not that big, may be in the range of 4-5 Mbps.
Bottomline, lwip140 gives much better performance on Rx side. On Tx side, with zero copy it gives great performance. On the Tx side, without zero copy, its performance is worse than lwip130.
Any comments on my observations?
regards
Anirudha
From: Kieran Mansley <address@hidden>
To: Mailing list for lwIP users <address@hidden>
Sent: Wednesday, 28 September 2011 5:04 PM
Subject: Re: [lwip-users] Fw: (no subject)
On 28 Sep 2011, at 12:15, Anirudha Sarangi wrote:
> Hi Kieren,
> Do you mean capturing the packets in wireshark and sending you the log?
Exactly. Please send the pcap file, not just the textual
log.
Kieran
_______________________________________________
lwip-users mailing list
address@hiddenhttps://lists.nongnu.org/mailman/listinfo/lwip-users