On Tuesday, 6 November 2018 14:09:14 PST René J. V. Bertin wrote: > Thiago Macieira wrote: > > Off-topic: no one uses bzip2 anymore. It's slow to compress, slow to > > decompress and produces worse results than xz. > > Xz is even slower, and on the machine these numbers came from that > difference is more important in this case.
Don't use -9 then. Try using something between -3 and -6. In a test locally with a 250 MB source (I believe it was qtbase's .tar file), I got the following results: gzip -9: 60.2 MB @ 22.16s bzip2 -9: 50.2 MB @ 25.26s xz -2: 49.4 MB @ 34.28s zstd -14: 49.0 MB @ 20.16s zstd -19: 45.9 MB @ 52.36s xz -6: 44.4 MB @ 99.19s xz -9: 42.5 MB @ 98.28s More importantly, the decompression times: gzip took 0.84s, zstd 0.30s and xz 2.81s. But bzip2 needed 6.6s. I'm adding Zstandard as an alternative to Zlib in Qt: https://codereview.qt-project.org/244431 https://codereview.qt-project.org/244432 > > Both are -O3 -march=native -g1 builds. So yes, the Clang build is smaller, > > but not significantly so. > > You know that significant is not a synonym for considerable, right? ;) I know. But: negligible < significant < considerable I'm claiming that the size is less than what you claim to be a problem. > > takes longer to compile or increases the size considerably", you don't > > really care about size. > > Off-topic, but if I can get the same performance with a smaller size, why > opt for the larger size? Because you can't. > > Clang carries 9793421 bytes of debug information, while GCC produces > > 13951906. That's a much bigger difference. > > I know; most of my builds do have debug info so this is important to me. > I should look into using separate debug info sometime, but not if it gives > something comparable to the .dSYM folders that tend to litter my > directories. I hate that for some reason. That's why you should strip them out and compress them. Store them where you may need them (possibly never). -- Thiago Macieira - thiago.macieira (AT) intel.com Software Architect - Intel Open Source Technology Center _______________________________________________ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
