can't select time-based sampling(it is grey)

[softarts]

just noticed I can't select time-based sampling(it is grey) on Linux(suse9,xeon)
I remember it is available on Windows version(xp,Core2)
anyone know the reason?

add comments:
just check the vtune book
it said can think of time-based is another form of event-based sampling
what does it mean?

[Peter_W_Intel]

Quoting - softarts

just noticed I can't select time-based sampling(it is grey) on Linux(suse9,xeon)
I remember it is available on Windows version(xp,Core2)
anyone know the reason?

add comments:
just check the vtune book
it said can think of time-based is another form of event-based sampling
what does it mean?

You are right!

VTune Analyzer for Linux* doesn't provides OS timer for sampling. It's hard to say why, but this is a design decision.

The user can useevent-based sampling to collect data, it has similar function like as OS timer interruption.

If you have 2G frequencyCPU, use CPU clock asinterval - there isevent count register, you can set 2,000,000,000/1,000 =2,000,000 to event counter register. That means after 2,000,000 CPU clockticks - one sample will be captured, 1000 samples will be collected per second. This method is much better (precious) than use OS Timer.

Hopefully I have answered your questions. (See more in OLH)

Regards, Peter

[Vladimir_T_Intel]

Originally there was no appropriate implementation of precise OS timers on Linux (as opposite to Windows), so the VTune sampling was restricted to event-based sampling (EBS) by design.

Peter explained very well how to use EBS as a time-based sampling.