for one of query total duration is 00:08:21 , but its showing REQ CPU as 986.16.
as pef user manual
|REQ CPU||Number of CPU seconds needed to run the query|
that means 986.16 seconds i.e 16.436 minustes. but query duration itself 8 minuts 21 secods , how come its possible ,experites can you please clear my doubt.
CPU seconds <> clock seconds
There's more than one CPU in a your system, e.g. if you got 100 CPUs there are 100 CPU-seconds per second.