I use it a lot, but I use automated tools for it, such as and and various hardware-vendor-supplied things.The reason I prefer automated tools over manual sampling for the work I do is. It has the advantage of measuring the CPU's usage by wall-clock time, which is what matters for interactivity, and getting callstacks with each sample lets you see why a function is being called. Callstack sampling is a very useful technique for profiling, especially when looking at a large, complicated codebase that could be spending its time in any number of places. (If the number of samples is increased to 20, the chance of seeing it two or more times increases to more than 99%.) So it hasn't been precisely measured, but it has been precisely found, and it's important to understand that it could easily be something that a profiler could not actually find, such as something involving the state of the data, not the program counter. If you're in the 14% who don't see it, just take more samples until you do. The general rule is if you see something you could fix on two or more samples, it is worth fixing.In this case, the chance of seeing it in 10 samples is 86%.
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