project property----Duration Estimation

[Linan_H_]

    I'm using Intel Vtune Amplifier XE to to profiling jobs and I'm confused about the selection of Duration Estimation in Project Property. If I choose Between 1min and 15min and enable multiple runs, does it mean that the duration time of multiple runs is between 1min and 15min or the single run time of target application is between 1min and 15min?

[TimP]

You don't normally need to make multiple runs when the individual runs are longer than 1 minute (assuming a sane choice of number of events).  In my experience, if you have a large number of threads, you will need to choose a larger duration estimate if that is your method for controlling sampling rate.  It's mainly a matter of what works best for your cases.

[Robert_L_Intel1]

Hi Linan -

To clarify just in case you might be misunderstanding this option:  This feature setting is related to the multiplexing behavior of the VTune™ Amplifier XE collector.  There is a metric you can use to help you decide whether or not multiplexing is causing a problem in the data.  It's the MUX Reliability value and has a range from 0 to 1.

If the value is high (i.e. .9), then you are okay and have good data.  If low, then you might consider enabling the "allow multiple runs" option and/or modifying other aspects of the collection to improve the accuracy of the data.

This is all about the fidelity of the data, though, and not necessarily the number of processes or jobs.

MUX Reliability
https://software.intel.com/en-us/node/537540

[David_A_Intel1]

Hi Linan:

These two options have nothing to do with each other.  The "Duration estimate" is a way for you to inform the VTune Amplifier about how long you expect the application to run with the specified workload.  Based on your "estimate", VTune Amplifier can make adjustments so that the amount of data still provides insight into your application's performance but doesn't collect so much data that it impacts VTune Amplifier's responsiveness.

The multiple runs option has to do with event-based sampling, only, and is more involved.  I prefer to refer you to the help topic for an explanation.  Enabling multiple runs, to increase event accuracy, does require that VTune Amplifier launch your application multiple times, but only one instance at a time.

Hope that helps.