Sampling v. tracing

1 · Dan Luu · Jan. 24, 2016, midnight
Perf is probably the most widely used general purpose performance debugging tool on Linux. There are multiple contenders for the #2 spot, and, like perf, they're sampling profilers. Sampling profilers are great. They tend to be easy-to-use and low-overhead compared to most alternatives. However, there are large classes of performance problems sampling profilers can't debug effectively, and those problems are becoming more important. For example, consider a Google search query. Below, we have a d...