On Tue, 2010-08-03 at 19:20 -0400, Karthik Vadambacheri Manian wrote: > So my questions are: > 1) Why do checksum errors occur even though I run everything in a > virtual machine and no hardware is involved? How can I reduce this?
I would guess a bug in your system. To reduce it fix the bug! For example, if there was a problem with a packet buffer being reused before the previous data had been sent you would see the data in the first packet corrupted with contents from a later one. The checksum would now show up this error. I would look at the packets (through a packet capture) that have checksum errors and see if it's either that the payload is incorrect (e.g. for each iteration set payload of your ping-pong packets to the number of the iteration and look for values out of order) or if the checksum has been computed wrongly. > 2) How can I prevent acknowledgements from missing so that > retransmissions can be avoided? Packets can be dropped or not sent for lots of reasons. The most obvious would be a shortage of packet buffers. You can use the LWIP_STATS code to monitor most of lwIP's internal resources and then when you print out the output it will show what (if anything) has been exhausted. You can then tune the allocation of resources to provide enough. > > 3) Some general tips on increasing performance with LWIP is much > appreciated. Take a look at the lwIP wiki - Simon wrote a good introduction to this a few months ago. Kieran _______________________________________________ lwip-users mailing list [email protected] http://lists.nongnu.org/mailman/listinfo/lwip-users
