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REVISION SUMMARY All benchmarks create a relatively large directory tree and then watch that recursively. On my system, the timings are: RESULT : KDirWatch_UnitTest::benchCreateTree(): 34.2 msecs per iteration (total: 342, iterations: 10) PASS : KDirWatch_UnitTest::benchCreateWatcher() RESULT : KDirWatch_UnitTest::benchCreateWatcher(): 13.6 msecs per iteration (total: 137, iterations: 10) PASS : KDirWatch_UnitTest::benchNotifyWatcher() RESULT : KDirWatch_UnitTest::benchNotifyWatcher(): 113.7 msecs per iteration (total: 1,138, iterations: 10) Note that this time includes wait/sleep time and the latency induced by the kernel for the inotify events to arrive. Measuring on-CPU time can be done by passing `-perf` to the benchmarks: PASS : KDirWatch_UnitTest::benchCreateTree(): RESULT : KDirWatch_UnitTest::benchCreateTree(): 165,910,830.4 CPU cycles per iteration (total: 1,659,108,304, iterations: 10) PASS : KDirWatch_UnitTest::benchCreateWatcher() RESULT : KDirWatch_UnitTest::benchCreateWatcher(): 64,014,469.8 CPU cycles per iteration (total: 640,144,699, iterations: 10) PASS : KDirWatch_UnitTest::benchNotifyWatcher() RESULT : KDirWatch_UnitTest::benchNotifyWatcher(): 316,077,005.5 CPU cycles per iteration (total: 3,160,770,055, iterations: 10) The first benchmark measures the time it takes to create the large directory. See below for why this is useful information. The second measures how long it takes to add the root dir and its contents recursively. The third one touches all files in the tree and measure how long it takes until all dirty signals arrive. If you subtract that measurement from the third benchmark, you arrive at the overhead imposed by KDirWatch. At this point, it's quite high! REPOSITORY R244 KCoreAddons REVISION DETAIL https://phabricator.kde.org/D9822 AFFECTED FILES autotests/kdirwatch_unittest.cpp To: mwolff, dfaure Cc: #frameworks