In the DS-5 Streamline (Professional 5.19.0) how can I change the "counter" that was used to calculate the number of samples (column Self) in the Functions/Code view?
Consider the scenario where I've profiled an application using several counters (e.g: clock cycles, branch instructions, cache behavior, etc). Is it possible to visualize (in call paths / functions / code / etc) the number of samples collected only for a subset of these events (e.g. clock cycles)?
Thank you,
Hi again, this time it's my turn to apologise for the late answer. I was on holiday for the last 2.5 weeks.
The Threshold Value of 10K means that a sample is taken every time the "clocks cycle counter" reaches 10K, or every 10,000 clock cycles. At this point the CPU is interrupted, gator takes control and samples the value of the PC and unwinds the call stack (if you have enabled that setting). This information is then used to generate the Functions, Code and Call Paths tables (that's the number of samples displayed). The Threshold Value setting enables you to manually trade in data accuracy with overhead.
Note that the counter values displayed in the Timeline view are read at context switches, not at "sampling time", so the x axis still shows time and the counter values are accurate. The filtering over time using the callipers also works.
The CPU Activity counter is always generated because it is worked out by the tool from the context switch information without incurring extra overhead on the target (i.e. the overhead of reading a hardware counter at the context switch). However, I also see that you cannot hide in the report (unlike other counters). I'll pass the feedback to engineering to see if they can make it removable.
Cheers, Javier