write performance is very lower than write performance in XGBE enviroment

[jumpapex]

when using iscsi-pf, I could get read throught at 600MB/S with argument(-m 4 -b 128) in XGBE enviroment. after modify iscsi-pf to test write(just zero memory), the throughput is no more than 300MB/S.

BTW, target just read/write data to memory.

Please kindly give some suggestions to improve write throughput, or it is expected?

Thanks!