Index: lnt/trunk/docs/tests.rst =================================================================== --- lnt/trunk/docs/tests.rst +++ lnt/trunk/docs/tests.rst @@ -253,6 +253,33 @@ and the ``--cmake-define`` flag allow you to change how LNT configures cmake for the test-suite run. + +Capturing Linux perf profile info ++++++++++++++++++++++++++++++++++ + +When using the CMake driver in the test-suite, LNT can also capture profile +information using linux perf. This can then be explored through the LNT webUI +as demonstrated at +http://blog.llvm.org/2016/06/using-lnt-to-track-performance.html . + +To capture these profiles, use command line option ``--use-perf=all``. A +typical command line using this for evaluating the performance of generated +code looks something like the following:: + + $ lnt runtest test-suite \ + --sandbox SANDBOX \ + --cc ~/bin/clang \ + --use-cmake=/usr/local/bin/cmake \ + --use-lit=~/llvm/utils/lit/lit.py \ + --test-suite ~/llvm-test-suite \ + --benchmarking-only \ + --build-threads 8 \ + --threads 1 \ + --use-perf=all \ + --exec-multisample=5 \ + --run-under 'taskset -c 1' + + Bisecting: ``--single-result`` and ``--single-result-predicate`` ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++