4.7 Events-based sampling

By default, Streamline records a sample at an interval determined by the Sample Rate drop-down menu in the Capture Options dialog box. But you can override this behavior and set Streamline to do events-based sampling, enabling you to customize which inefficiencies you want to highlight with the sampling data.

With events-based sampling, Streamline samples only when the selected event is triggered a number of times equal to the value in the Threshold field of the Counter Configuration dialog box, and does so for each core on your target. For example, to trigger a sample every time a core causes 500 L2 cache misses, select L2 miss from the Events to Collect list and enter 500 in the Threshold field. Given an adequate capture session, the Samples statistic contained in many of the Streamline reports now indicates which processes and functions are the potential cause of inefficient caching.

Warning

Events-based sampling is only possible when the PMU on the target hardware can generate interrupts.
Related tasks
Opening the Counter Configuration dialog box
Adding new events to the Events to Collect list
Removing events from the Events to Collect list
Setting up events-based sampling
Related reference
Counter Configuration toolbar options
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