Ethernet Shield Performance

Forum 2005-2010 (read only) Hardware Interfacing
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I'm going through the thought process for a new project which would require the Ethernet shield.

Sadly, I don't have one with which to test, and can't find any statistics on it, so I was hoping y'all could help: What is the maximum expected sustained rate for reading from a single Socket connection?

Specifically, assuming no processing of the data on the part of the arduino; just reading the data from the ethernet shield as rapidly as possible.

I suspect there's an absolute upper bound of 1MB/sec, but I need to know what the actual reasonable value is for sustained reading.

Thanks y'all.

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For anyone that would find this useful, the highest I've gotten it as far as sending data is ~5kilobytes/second. Past that and painfully long slow downs occur.

That, and there was apparently someone else out there with the same problem/question, http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1258127723/9 .

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My stance since your linked question hasn't changed, if you want faster, its likely an Arduino isn't up to the job in the first place.

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I have just started playing with my Ethernet shield, and I wrote an RSS feed reader for Slashdot. Turns out I can achieve only 4.70 KB/s according to my code. I dug into the Ethernet library a little, and it appears that every time there is data to read (at least in this experience) there are 1024 bytes from available(), yet the library only allows you to read 1 byte at time... I'm thinking that there should be a way to grab more than just one byte at a time, and that should improve the performance...

I looked at the Ethernet2 library, but haven't tried it yet, though it also presents the same 1 byte at a time interface.

I will have to play with that a bit and see if I can pull the pointer out of the depths of that library, and maybe just work with that directly. Has anyone ever tried something like that before?