Re:Potato paradox
by ot on Thursday July 16, 2015 @08:34AM
(#9896773)
This is the obvious strategy, but it's not always applicable.
For example when profiling a long-running service, or a kernel, there's no "absolute time it needs", you need other proxies of running time such as the CPU usage percentage, but even that is not noise-free.
So if you just run "perf" on it, you need to be aware of this fallacy.
Re:Potato paradox
by blueblob on Thursday July 16, 2015 @09:41AM
(#9897068)
I am pretty much a novice in program optimization, but doesn't `perf` sample clock cycles? So in effect CPU usage percentage doesn't matter as much since it's not using wall clock time?
For example when profiling a long-running service, or a kernel, there's no "absolute time it needs", you need other proxies of running time such as the CPU usage percentage, but even that is not noise-free.
So if you just run "perf" on it, you need to be aware of this fallacy.