[07:50] <mgedmin> laptop died a swappy death
[07:51] <mgedmin> I upgraded two laptops to ubuntu gnome 14.10 and both do this about once a week :(
[07:51] <mgedmin> both run without swap because both have SSDs
[07:51] <mgedmin> one has 8 gigs of ram, the other has 2 gigs
[07:53] <darkxst> mgedmin, I am confused how can a laptop die a swappy death when its not using swap?
[07:54] <darkxst> you shouldnt have any problems with 8gb and no swap, 2gb might be problematic
[07:54] <mgedmin> HDD LED on, computer nonresponsive (caps lock takes 60 seconds between keypress and led being on), mouse movement limited to 1/2px per minute
[07:54] <mgedmin> the onset is instant
[07:54] <mgedmin> waiting 20 seconds for some help (OOM killer?) doesn't help
[07:54] <mgedmin> I don't _know_ that it was OOM
[07:55] <darkxst> its booting into shell?
[07:55] <mgedmin> what do you mean?
[07:55] <darkxst> like you are in gnome-shell and its doing this?
[07:55] <mgedmin> yes
[07:56] <mgedmin> I'm looking at atop logs
[07:56] <darkxst> is it really using swap though, or something else flogging drives
[07:56] <darkxst> mgedmin, or iotop
[07:56] <mgedmin> it shows the disk being busy between 92 and 102%, doing mostly reads at 230 MB/s
[07:56] <mgedmin> this is forensic study now, I had to alt-sysrq-s,u,b reboot
[07:57] <mgedmin> atop writes a snapshot of the system state every 10 minutes to a binary log file
[07:57] <mgedmin> when the laptop became non-responsive gnome-shell's clock said 09:14
[07:57] <mgedmin> I turned it off at about 09:37
[07:58] <mgedmin> well, I hit Alt-SysRq-K at that point to kill X
[07:58] <mgedmin> the S,U,B was at 09:39
[07:58] <mgedmin> which is lucky, since atop wrote its last system snapshot at 09:38
[07:58] <darkxst> I hit a similar issue caused by media-scanner, but you shouldnt have that installed on Ubuntu-GNOME unless you also have ubuntu desktop installed
[07:59] <mgedmin> let's look at the 09:28 snapshot: I have 4.1G in cache, 112M free, 0 swap, sda is busy 102%, reading at 250 MB/s
[07:59] <darkxst> can you ssh in and find what is causing the reads?
[07:59] <mgedmin> processes reading from disk include: skype (8%), VBoxHeadless (7%), chromium-browser (7%) kswapd0 (6%)
[07:59] <mgedmin> basically everything is reading from disk
[08:00] <mgedmin> whoa, the page scan rate is 1603e6
[08:00] <mgedmin> at 09:08:32 it was "PAG |  scan  76411 |"
[08:00] <mgedmin> 10 minutes later it was 2744e5
[08:00] <mgedmin> ten minutes later it was 1603e6
[08:01] <mgedmin> and ten minutes later it was 1630e6
[08:01] <mgedmin> my hypothesis: the kernel decides it needs to free some ram, so it starts discarding mapped executable pages
[08:01] <mgedmin> and then all the running apps have to read them back in all the time
[08:02] <mgedmin> which makes for 250 MB/s read rate and processes like Skype reading 13.5GB of data in a 10 minute window
[08:02] <mgedmin> if I had some swap, maybe the kernel would push some dirty pages out
[08:02] <darkxst> mgedmin, not too sure but you could try an older kernel and see if that helps
[08:03] <darkxst> I have to cook dinner, then head out for the night, ping me tomorrow
[08:11] <mgedmin> I want a system monitor applet in my gnome-shell
[08:12] <mgedmin> one that shows the amount of free memory I have and doesn't block the main gnome-shell thread
[08:41] <darkxst> mgedmin, my one is largely unmaintained now, and it does block unfortunately
[08:41] <darkxst> stupid libgtop doesn't have an async api
[08:41] <mgedmin> does gjs support threads?
[08:41] <darkxst> nope
[08:42] <darkxst> and it likely never will
[08:42] <mgedmin> jay
[08:42] <mgedmin> I used to use https://extensions.gnome.org/extension/120/system-monitor/ until I discovered that little gotcha with network filesystems going away
[08:42] <darkxst> most of the real GNOME libraries have async api's though
[08:43] <mgedmin> I don't think the kernel has an async version of statvfs, does it?
[08:43] <darkxst> heh, I just disabled network filesystems, since it was causing blocking on stale mounts
[08:43] <darkxst> well not just, ages ago
[08:49]  * mgedmin files https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1390358 and has no hopes of this being looked at seriously
[08:53] <darkxst> mgedmin, did this just start happening? or you only just upgraded to 14.10
[08:55] <mgedmin> before 14.10 it was "basically never" on my main laptop
[08:55] <mgedmin> after 14.10 it's about once a week
[08:55] <mgedmin> on my second laptop (2gigs of ram, a thinkpad x200, used as a media center at home) actually the same
[08:56] <mgedmin> it would run out of ram about once a week (gnome-shell memleak in 12.04), but I could recover with alt-f2 r
[08:56] <mgedmin> hey, it's now running 14.04, not 14.10
[08:56] <mgedmin> and when it freezes this way I can't recover with alt-f2 r, I have to alt-sysrq-s,u,b
[08:56] <mgedmin> so hm
[08:57] <darkxst> its pretty damn critical if you can't even switch to a VT
[08:57] <mgedmin> the media laptop typically freezes when my wife opens a youtube video
[08:57] <mgedmin> I can switch to a vt, if I'm patient enough
[08:57] <mgedmin> I can't log in, because  login it times out after 60 seconds without giving me a chance to enter my password
[08:58] <mgedmin> once, just once, I lived through this kind of disk storm
[08:58] <mgedmin> vmstat was funny to look at
[08:59] <darkxst> mgedmin, i bet, anyway Im out now