While using iperf to testing TCP performance, we found win7 machines with 82579LM NIC has inconsistent TCP performance result(some time 400mb/s some time 900mb/s, no other results).
On some machines, we fixed this problem by disable "interrupt moderation" to "high", problem fixed-> consistent TCP perf test result.
On some machines, non of our efforts have any effects: disable tcp offload etc.
Both OS and NIC driver are update to the latest.
Anyone saw this issue?