Hi Asim,
> -----Original Message----- > From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Asim Jamshed > Sent: Tuesday, June 28, 2016 2:41 PM > To: dev at dpdk.org > Subject: [dpdk-dev] Fwd: dpdk ixgbe PMD lro limits > > Hi, > > Apologies in advance if this question has been asked in the past. > > I have been performing mTCP-related tests on dpdk-16.04 with ixgbe PMD. I am > using 82599ES 10-Gigabit adapters for my experiments. I have a few queries > regarding LRO. > > 1) What is the theoretical maximum size of the Ethernet frame I can get from > the driver once LRO is enabled? In my experiments, I was seeing packet size as > high as 16KB. Can it be as high as ~2^16 bytes (iph->tot_len)? I'm not sure about if I understand your question correctly. Assume you're talking about the TCP segment after LRO. So, it's said there are no limitations on the maximum packet length. > > 2) Since the NIC is reassembling payloads (of one flow) into a single packet, > what does the Ethernet controller do with the tcp checksum field in the TCP > header? I am observing that each LRO packet has checksum value as zero? Is > that normal? I could not find any relevant documentation on the Web. That's expected. You can search 82599 datasheet. I think that's what you're looking for. > > Thanks in advance, > --Asim
