Re: Memory overcommit

["Vedran Furač" <vedran.furac@gmail.com>]

David Rientjes wrote:

> On Thu, 29 Oct 2009, Vedran Furac wrote:
> 
>>> We would know if you posted the data.
>> I need to find some free time to destroy a session on a computer which I
>> use for work. You could easily test it yourself also as this doesn't
>> happen only to me.
>>
>> Anyways, here it is... this time it started with ntpd:
>>
>> http://pastebin.com/f3f9674a0
>>
> 
> That oom log shows 12 ooms but no tasks actually appear to be getting 
> killed (there're no "Killed process 1234 (task)" found).  Do you have any 
> idea why?

That's /var/log/messages. I posted it and not dmesg because whole log
didn't fit dmesg buffer, here is waht i have (compare timestamps):

% dmesg|grep -i kill

[ 1493.064458] Out of memory: kill process 6304 (kdeinit4) score 1190231
or a child
[ 1493.064467] Killed process 6409 (konqueror)
[ 1493.261149] knotify4 invoked oom-killer: gfp_mask=0x201da, order=0,
oomkilladj=0
[ 1493.261166]  [<ffffffff810d6dd7>] ? oom_kill_process+0x9a/0x264
[ 1493.276528] Out of memory: kill process 6304 (kdeinit4) score 1161265
or a child
[ 1493.276538] Killed process 6411 (krusader)
[ 1499.221160] akregator invoked oom-killer: gfp_mask=0x201da, order=0,
oomkilladj=0
[ 1499.221178]  [<ffffffff810d6dd7>] ? oom_kill_process+0x9a/0x264
[ 1499.236431] Out of memory: kill process 6304 (kdeinit4) score 1067593
or a child
[ 1499.236441] Killed process 6412 (irexec)
[ 1499.370192] firefox-bin invoked oom-killer: gfp_mask=0x201da,
order=0, oomkilladj=0
[ 1499.370209]  [<ffffffff810d6dd7>] ? oom_kill_process+0x9a/0x264
[ 1499.385417] Out of memory: kill process 6304 (kdeinit4) score 1066861
or a child
[ 1499.385427] Killed process 6420 (xchm)
[ 1499.458304] kio_file invoked oom-killer: gfp_mask=0x201da, order=0,
oomkilladj=0
[ 1499.458333]  [<ffffffff810d6dd7>] ? oom_kill_process+0x9a/0x264
[ 1499.458367]  [<ffffffff81120900>] ? d_kill+0x5c/0x7c
[ 1499.473573] Out of memory: kill process 6304 (kdeinit4) score 1043690
or a child
[ 1499.473582] Killed process 6425 (kio_file)
[ 1500.250746] korgac invoked oom-killer: gfp_mask=0x201da, order=0,
oomkilladj=0
[ 1500.250765]  [<ffffffff810d6dd7>] ? oom_kill_process+0x9a/0x264
[ 1500.266186] Out of memory: kill process 6304 (kdeinit4) score 1020350
or a child
[ 1500.266196] Killed process 6464 (icedove)
[ 1500.349355] syslog-ng invoked oom-killer: gfp_mask=0x201da, order=0,
oomkilladj=0
[ 1500.349371]  [<ffffffff810d6dd7>] ? oom_kill_process+0x9a/0x264
[ 1500.364689] Out of memory: kill process 6304 (kdeinit4) score 1019864
or a child
[ 1500.364699] Killed process 6477 (kio_http)
[ 1500.452151] kded4 invoked oom-killer: gfp_mask=0x201da, order=0,
oomkilladj=0
[ 1500.452167]  [<ffffffff810d6dd7>] ? oom_kill_process+0x9a/0x264
[ 1500.452196]  [<ffffffff81120900>] ? d_kill+0x5c/0x7c
[ 1500.467307] Out of memory: kill process 6304 (kdeinit4) score 993142
or a child
[ 1500.467316] Killed process 6478 (kio_http)
[ 1500.780222] akregator invoked oom-killer: gfp_mask=0x201da, order=0,
oomkilladj=0
[ 1500.780239]  [<ffffffff810d6dd7>] ? oom_kill_process+0x9a/0x264
[ 1500.796280] Out of memory: kill process 6304 (kdeinit4) score 966331
or a child
[ 1500.796290] Killed process 6484 (kio_http)
[ 1501.065374] syslog-ng invoked oom-killer: gfp_mask=0x201da, order=0,
oomkilladj=0
[ 1501.065390]  [<ffffffff810d6dd7>] ? oom_kill_process+0x9a/0x264
[ 1501.080579] Out of memory: kill process 6304 (kdeinit4) score 939434
or a child
[ 1501.080587] Killed process 6486 (kio_http)
[ 1501.381188] knotify4 invoked oom-killer: gfp_mask=0x201da, order=0,
oomkilladj=0
[ 1501.381204]  [<ffffffff810d6dd7>] ? oom_kill_process+0x9a/0x264
[ 1501.396338] Out of memory: kill process 6304 (kdeinit4) score 912691
or a child
[ 1501.396346] Killed process 6487 (firefox-bin)
[ 1502.661294] icedove-bin invoked oom-killer: gfp_mask=0x201da,
order=0, oomkilladj=0
[ 1502.661311]  [<ffffffff810d6dd7>] ? oom_kill_process+0x9a/0x264
[ 1502.676563] Out of memory: kill process 7580 (test) score 708945 or a
child
[ 1502.676575] Killed process 7580 (test)


> Can you explain why Xorg is preferred as a baseline to kill rather than 
> krunner in your example?

Krunner is a small app for running other apps and do similar things. It
shouldn't use a lot of memory. OTOH, Xorg has to hold all the pixmaps
and so on. That was expected result. Fist Xorg, then firefox and
thunderbird.