I created a xperf log on Windows 8.1 x64. I can view it without any problems on Windows 8.1 x64. But when I open it wiht xperf on Windows 7 x64, the lift time of all processes is permanent, which means there is no processes start/stop during the log collection. It is wrong. My co-worker also met this problem on his machine. I am using xperf (WPA) version 6.3.9600.16384, which was installed a couple of weeks ago. It should be a pretty new version. Does anyone know how to solve the problem? 

By the way, I can't attach the xperf log here because there is some sensitive information. Sorry about that.

Thanks,

Pu