Yang Yang wrote: > > Why are you running two senders concurrently? The test is not intended > > to handle that case. > > Sorry for the inaccuracy of the description here, these two commands, > i.e. with or without GSO, cause the problem. The same goes for patch 2/3. > The problem is easily reproducible in the latest kernel, QEMU environment, E1000. > > bash# udpgso_bench_tx -l 4 -4 -D "$DST" > udpgso_bench_tx: write: Connection refused > bash# udpgso_bench_rx -4 -G -S 1472 -v > udpgso_bench_rx: data[1472]: len 17664, a(97) != q(113) > > bash# udpgso_bench_tx -l 4 -4 -D "$DST" -S 0 > udpgso_bench_tx: sendmsg: Connection refused > bash# udpgso_bench_rx -4 -G -S 1472 -v > udpgso_bench_rx: data[61824]: len 64768, a(97) != w(119) I still don't follow: are you running the tx and rx commands sequentially or in parallel? On different (virtual) hosts? > In one test, the verification data is printed as follows: > abcd...xyz > ... > abcd...xyz > abcd...opabcd...xyz > > This is because the sender intercepts from the buf at a certain length, > which is not aligned according to 26 bytes, and multiple packets are > merged. The verification of the receiving end needs to be performed > after splitting. The 26 bytes is a reference to the pattern printed by the test, which iterates over A-Z. Is your point that each individual segment starts at A, so that a test for pattern {ABC..Z}+ only matches if the segments size is a multiple of 26, else a the pattern will have discontinuities?