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A comment on Evaluation of CPU profiling tools: gperftools, Valgrind and gprof (2015).

Re:Evaluation of CPU profiling tools: gperftools, Valgrind a... by woadwarrior01 on Monday November 11, 2019 @03:39AM (#21503077)
Also worth mentioning here is perf[1], which is great for low overhead profiling. Also, perf profiles can be turned into profiles compatible with GCC and LLVM PGO to build optimized binaries based on production runs, using autofdo[2]. In my use case, the instrumentation overhead was too high to use regular profiling on production workloads.

[1]: https://en.m.wikipedia.org/wiki/Perf_%28Linux%29

[2]: https://github.com/google/autofdo

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Re:Evaluation of CPU profiling tools: gperftools, Valgrind a... by atq2119 on Monday November 11, 2019 @05:38AM (#21503654)
Don't forget Hotspot as a way to visualize perf results, which vanilla perf is unfortunately a bit lacking in: https://github.com/KDAB/hotspot
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Re:Evaluation of CPU profiling tools: gperftools, Valgrind a... by the8472 on Monday November 11, 2019 @06:07AM (#21503792)
Thank you, I have been looking for something that could display perf recordings as a swimming lane view for threads.
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Re:Evaluation of CPU profiling tools: gperftools, Valgrind a... by scott_s on Monday November 11, 2019 @10:38AM (#21505668)
For anyone looking to use perf, Brendan Gregg's page on it is the best resource I know of: http://www.brendangregg.com/perf.html
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Re:Evaluation of CPU profiling tools: gperftools, Valgrind a... by seminatl on Monday November 11, 2019 @11:11AM (#21505945)
Fun fact: the pprof tool that comes in gperftools can read perf data files, so you can use them together if you prefer pprof’s reporting.
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Re:Evaluation of CPU profiling tools: gperftools, Valgrind a... by gnufx on Monday November 11, 2019 @03:52PM (#21508789)
perf and its ilk are obviously useful, but you need to be aware of several cans of worms with sampling hardware counters, in particular. These include the timing mechanism for sampling, the documentation and intrinsic usefulness of particular counters, and issues with multiplexing more than what can be used simultaneously. For multiplexing see, for instance, https://www.research.manchester.ac.uk/portal/files/59933625/...
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