On 16/06/14 19:47, Goffredo Baroncelli wrote: > Hi all, > > in this blog [1] I collected all the results of the tests which I > performed in order to investigate a bit this performance problem > between systemd and btrfs. I had to put these results in a blog, > because there are several images. Below a brief summary.
> The test #1 highlight the problem. It shows that the boot time may > require up to 50 seconds. During the reboots the number of extents of > the file system.journal increases up to 6000. De-fragmenting the > system.journal file the boot time decreases by ~20 seconds. My > conclusion is that in BTRFS the fragmentation of this file increases > the boot time. > > The test #6 and #7 suggested that the fsync(2) amd posix_fallocate(3) > calls aren't the root cause of the problem. Even without these the > system.journal file still fragments. > [1] > http://kreijack.blogspot.it/2014/06/btrfs-and-systemd-journal.html Very good demonstration and summary, thanks. The charts very clearly show the correspondence between time-to-boot and the level of fragmentation. ... And I thought Linux was getting ever faster to boot! Regards, Martin _______________________________________________ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
