> On June 24, 2013, 9:19 a.m., David Faure wrote: > > kdecore/services/kmimetype.cpp, line 316 > > <http://git.reviewboard.kde.org/r/111050/diff/3/?file=165328#file165328line316> > > > > I can't review this. It completely forks an existing method > > (findByUrlHelper), which is already supposed to have a fast path (not > > reading the contents of the file). So why not improve the existing method, > > rather than fork it? With this patch, I can't see what you changed compared > > to the original method, and what might possibly be missing (= regression).
Right, a very valid case. However considering the speedup has dropped down to just ~2x... and given the possibility's of possible regressions in dead code. I'm not keen on making a new patch. If you think it's worth, I'll make a new one. If you think it's not then I'll discard this reviewrequest. > On June 24, 2013, 9:19 a.m., David Faure wrote: > > kdecore/services/kmimetyperepository.cpp, line 594 > > <http://git.reviewboard.kde.org/r/111050/diff/3/?file=165329#file165329line594> > > > > This can't possibly be a speedup :-) > > > > In fact I don't see what the parsing of the globs file has to do with > > checking that the essential mimetypes exist (they typically don't have > > globs, even). A leftover from previous patch versions. - Mark ----------------------------------------------------------- This is an automatically generated e-mail. To reply, visit: http://git.reviewboard.kde.org/r/111050/#review34953 ----------------------------------------------------------- On June 23, 2013, 9:21 p.m., Mark Gaiser wrote: > > ----------------------------------------------------------- > This is an automatically generated e-mail. To reply, visit: > http://git.reviewboard.kde.org/r/111050/ > ----------------------------------------------------------- > > (Updated June 23, 2013, 9:21 p.m.) > > > Review request for kdelibs, David Faure and Frank Reininghaus. > > > Description > ------- > > Hi, > > I've recently seen Frank Reininghaus do his best in speeding up the rendering > in dolphin with regards to the app icons. And trying to prevent icon > flickering between "unknown" and the actual icon. > > While reading his posts on the mailing list i was beginning to wonder: "is > fast mime detection actually fast"? While it was certainly faster then "slow" > mime detection, it still didn't really seem fast to me. A small benchmark app > hat ran fast mime detection in /usr/bin took ~40ms to complete. That's for > just 2656 items. > > After quite a bit of profiling i managed to to bring the duration down from > ~40ms to ~3ms sometimes ~4ms. That's well over 10x faster. > Mime detection by extension (like "file.tar.bz") is done as follows: > > file.tar.bz > Loop - find first dot > - "tar.gz" > if that matches a mime type then it's returned if it doesn't then it proceeds > on to the next dot: > - next dot: "gz" > if that matches.. return. > Otherwise it will return the default mime type. > > I am getting an inconsistency. Using the unpatched fast mime detection on a > file like: "test.tar.gz" gets detected as "application-x-compressed-tar" > where the patched version detects it as "application-gzip". The slow and > detailed mime detection detects the same file as > "application-x-compressed-tar". What should it be? application-gzip or > application-x-compressed-tar? > > Note: This improved detection does expect folders to end with a "/". > Otherwise they will be detected as application-octet-stream (the default). > But i think this is common sense to let folders end with a "/". If any apps > that don't do that, they should fix it i suppose. > > Best thing, it's all internal and private api change. No public function is > changed. > > All feedback is welcome! If possible, i would like to put this in KDE 4.11. > > > Diffs > ----- > > kdecore/services/kmimetype.h bc35bcf > kdecore/services/kmimetype.cpp d748523 > kdecore/services/kmimetyperepository.cpp f56f48e > > Diff: http://git.reviewboard.kde.org/r/111050/diff/ > > > Testing > ------- > > Tested this using just output comparison between the old version and the new > implementation. It works just fine. > kurlmimetest output: > ********* Start testing of KUrlMimeTest ********* > Config: Using QTest library 4.8.4, Qt 4.8.4 > PASS : KUrlMimeTest::initTestCase() > PASS : KUrlMimeTest::testURLList() > PASS : KUrlMimeTest::testOneURL() > PASS : KUrlMimeTest::testFromQUrl() > PASS : KUrlMimeTest::testMostLocalUrlList() > PASS : KUrlMimeTest::cleanupTestCase() > Totals: 6 passed, 0 failed, 0 skipped > ********* Finished testing of KUrlMimeTest ********* > > > Thanks, > > Mark Gaiser > >
