On 12 April 2017 at 06:33, Terry Barnaby <terry@xxxxxxxxxxx> wrote: > With a 50s boot to login screen that gives: > > Startup finished in 2.069s (kernel) + 3.395s (initrd) + 25.451s (userspace) > = 30.915s > > 12.391s systemd-journal-flush.service > 8.049s lvm2-monitor.service > 7.862s systemd-udev-settle.service > 7.502s dev-sda5.device > 6.231s packagekit.service > 5.528s abrtd.service > 5.030s accounts-daemon.service > 4.937s boapns.service > 4.245s NetworkManager.service > 2.751s systemd-logind.service > ... > This looks like the old bug with journal flushing drastically slowing boot - https://bugzilla.redhat.com/show_bug.cgi?id=1006386 - which I think was partly mitigated until the removal of readahead made it worse again. The problem is (a) flushing the journal to disk (which involves reading the old journal from disk) when there's a lot of other i/o going on takes too long; (b) any process that tries to log to the journal while this is going on will stall. That's why you see multiple services taking seconds in the blame, even ones that should be taking almost no time. Before I got a SSD I used to workaround it by crudely reading in the journal before flushing it: $ cat /etc/systemd/system/systemd-journal-flush.service.d/preread-journal.conf [Service] ExecStartPre=/bin/dd if=/var/log/journal/%m/system.journal of=/dev/null Hopefully this will improve things for you. > I don't think there are any issues with this particular laptop. All of my > other 10+ Fedora25 KDE/Plasma5 systems are basically the same, slow to get > to a logged in condition these days. > It just appears that Fedora Linux and particularly the KDE/Plasma software > is getting grossly inefficient and requires more and more random disk > accesses than before. I guess SSD's are covering this up to a fair extent, > but with rotating disk file systems and network files systems this doesn't > seem good to me. All this stuff that shows up the the systemd-analyze blame is largely independent of KDE/Plasma. Though I do expect that sddm could start up a little faster, and obviously the long login time is Plasma's responsibility. The login time might get better over time, but either way a SSD is a magic bullet here. Something I've found useful to understand boot times is "systemd-analyze plot > blah.svg" to get a bootchart, which might give you visual clues about bottlenecks. Particularly as you say there's a 50 second boot to login screen but systemd-analyze only reports 30 seconds - it wold be interesting to see what happens between when sddm.service is activated and the end of the bootchart. _______________________________________________ kde mailing list -- kde@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to kde-leave@xxxxxxxxxxxxxxxxxxxxxxx
