Profiling with Ctrl-C (2024)
4 months ago
- #profiling
- #debugging
- #performance
- Ctrl-C profiling is a simple yet effective method for identifying performance issues in programs, especially for 'stupid problems' encountered by lazy people in unfriendly environments.
- The author shares personal experiences where Ctrl-C profiling helped identify issues like slow JSON parsing in debug builds and slow GDB performance with LLD linker, leading to quick fixes.
- Ctrl-C profiling is praised for its simplicity, requiring less setup than traditional profilers, and being applicable in environments where standard profilers might not work, such as on chips without standard OS support.
- Despite its advantages, Ctrl-C profiling has limitations, such as being a sampling profiler with low frequency, making it unsuitable for detecting very small changes across a program or tail latency issues.
- The article contrasts Ctrl-C profiling with more sophisticated profiling methods, highlighting scenarios where traditional profilers are necessary, such as identifying small performance regressions or analyzing multi-threaded systems.
- The author concludes by endorsing Ctrl-C profiling as a primitive yet often surprisingly effective tool, especially when compared to more complex and sometimes overkill profiling solutions.