woah....wth just happened?

[xSauronx]

ok, this is running etch with XFCE on my inspiron 1000

ive noticed the memory usage being particularly high on this since i started the fresh install thursday night

i havent been too bothered by it, just left a load monitor with cpu/mem scales on my panel and figured id play around with some things this week to see what was causing it

so im listening to some music on vlc, and browsing with firefox and my mem usage is ~680 of 692mb, and acting a bit sluggish because of it

then my system freezes for a moment and....now its down to 150/692

wha'happend? it hasnt done this before at all over the last few days, not that im complaining, but i cant help but be curious

 

[Nothinman]

That is strange, it's possible to free the cache memory by doing "echo 1 > /proc/sys/vm/drop_caches" but I can't think of anything that would cause that to happen without your intervention. Did you check dmesg?

 

[drag]

Sounds like you have a runaway process that is eating up your RAM and then when your system runs out of ram your kernel goes into a tizzy (makes your system lock up as it goes into emergency mode.. spending all it's time going through memory pages looking for ones to discard) before unleashing the OOM killer.

The OOM killer then finds the offending process and kills it, freeing up the ram.

That's what it seems like anyway. It's happened to me a few times as I tried to do things that required massive amounts of RAM.

Is it killing off Firefox?

Got a swap partition? (you should. If you don't and you don't feel like repartitioning then it's possible to use a file windows-style) That will give you enough time to much around in the now-sluggish system to find the offending process and kill it yourself. OOM killer is messy and may occasionally nail the wrong thing causing loss of data.

Probably what I'd do is keep a xterm with 'top' running so that you can find which process is the one eating up the ram.

That's my guess.

 

[Sunner]

Originally posted by: drag
Sounds like you have a runaway process that is eating up your RAM and then when your system runs out of ram your kernel goes into a tizzy (makes your system lock up as it goes into emergency mode.. spending all it's time going through memory pages looking for ones to discard) before unleashing the OOM killer.

The OOM killer then finds the offending process and kills it, freeing up the ram.

That's what it seems like anyway. It's happened to me a few times as I tried to do things that required massive amounts of RAM.

Is it killing off Firefox?

Got a swap partition? (you should. If you don't and you don't feel like repartitioning then it's possible to use a file windows-style) That will give you enough time to much around in the now-sluggish system to find the offending process and kill it yourself. OOM killer is messy and may occasionally nail the wrong thing causing loss of data.

Probably what I'd do is keep a xterm with 'top' running so that you can find which process is the one eating up the ram.

That's my guess.

Didn't they take out the OOM killer in late 2.4 somewhere?
I remember it causing some problems for us in 2.4.18, and poking around the net, I came across some LKML posting about it being removed in 2.4.2x something.

Then again, if a process runs amok, it might just segfault after it eats the RAM.
In either case, yeah, it's probably a process running wild, eating RAM and pushing out cache, then getting killed or segfaulting, handing your memory back.

Have you checked in top to see if any application is gradually eating more and more memory?
Seeing near 100% memory usage is perfectly normal due to caching, so don't worry about that, if you start swap thrashing though, performance will take a dive fast.

 

[xSauronx]

thanks for the replies

i posted and went to bed, but my kids are sick so ill play around today while im home and try to narro--

it just rebooted for no reason 🙁

anyway, ill play around with it today
im wondering if my debian hates my laptop. im having some weird issues i never had with xubuntu. i get more firefox crashes, text input is farked up, and lousy memory usage (yes, i have a swap partition)

thanks for the suggestions, everyone, ill take my time today to figure out what i can 🙂

 

[Nothinman]

Didn't they take out the OOM killer in late 2.4 somewhere?

Nope, it's still there in 2.4 and 2.6.

 

[drag]

Did the laptop reboot while you were there? Or did it reboot while you were away?

I beleive that if it gets a kernel panic or whatnot it may wait a couple minutes then reboots. Not sure.



I could be driver issues. I'd keep a eye on dmesg logs to see if you get any oops and such things. Especially if your running propriatory drivers (ndiswrapper or nvidia drivers, etC)


Also running memtest would be a good idea. If you go 'apt-get install memtest86' (or memtest86+, not sure what the difference is) and then run 'update-grub' it will add memtest86 to the boot menu. I just always try that first, just to see if there is a issue there.

 

[xSauronx]

Originally posted by: drag
Did the laptop reboot while you were there? Or did it reboot while you were away?

I beleive that if it gets a kernel panic or whatnot it may wait a couple minutes then reboots. Not sure.



I could be driver issues. I'd keep a eye on dmesg logs to see if you get any oops and such things. Especially if your running propriatory drivers (ndiswrapper or nvidia drivers, etC)


Also running memtest would be a good idea. If you go 'apt-get install memtest86' (or memtest86+, not sure what the difference is) and then run 'update-grub' it will add memtest86 to the boot menu. I just always try that first, just to see if there is a issue there.

ill try the memtest thing, it rebooted mid-post, heres the relecant entry from /etc/var/log/syslog (is there another one i should look at?)

Apr 10 07:52:56 actium -- MARK --
Apr 10 07:57:58 actium syslogd 1.4.1#18: restart.
Apr 10 07:57:58 actium kernel: klogd 1.4.1#18, log source = /proc/kmsg started.
Apr 10 07:57:59 actium kernel: Linux version 2.6.18-4-686 (Debian 2.6.18.dfsg.1-12)

just a restart, out of nowhere, and then on it goes :/ nothing before that for half an hour since i had logged in

aside from running gAim for an hour or so today, the only thing ive had open is firefox. ill spare you the multitude of notes, but memory usage climbed, firefox never used (according to top) more than 14.5% of ram.

again, according to top, memory usage was climbing. things got sluggish, i rebooted and am trying opera now (the menus are fugly, meh, a qt thing i guess?)

cant see how it could be firefox, ill reboot and run memtest ad see what i get

edit: memtest found no problems

 

[drag]

Look at /var/log/messages and /var/log/messages.0

See if anything is showing up in there.

 

[xSauronx]

Originally posted by: drag
Look at /var/log/messages and /var/log/messages.0

See if anything is showing up in there.

nothing about a restart, just an end of dmesg stuff, then a login after i rebooted (skipping the reboot part, meh)

 

[drag]

Well unless we get some sort of log or dmesg output that shows anything, something, that is happenning that is causing your system to hang like this then it's giong to be a dead end for us.

I have a few ideas. Like it could be that your system's laptop drive is spinning down but having a hard time spinning up. Your system writes stuff out to the FS and it gets stored in cache. The drive doesn't spin up so cache keeps getting bigger and bigger till the system hangs, something triggers the laptop drive to kick in, and then cache is written to disk free'ing up all that ram.

Try disabling laptop-mode then
/etc/init.d/laptop-mode stop

 

[xSauronx]

Originally posted by: drag
Well unless we get some sort of log or dmesg output that shows anything, something, that is happenning that is causing your system to hang like this then it's giong to be a dead end for us.

I have a few ideas. Like it could be that your system's laptop drive is spinning down but having a hard time spinning up. Your system writes stuff out to the FS and it gets stored in cache. The drive doesn't spin up so cache keeps getting bigger and bigger till the system hangs, something triggers the laptop drive to kick in, and then cache is written to disk free'ing up all that ram.

Try disabling laptop-mode then
/etc/init.d/laptop-mode stop

i will if it happens again. thanks 🙂

 

[Nothinman]

nothing about a restart, just an end of dmesg stuff, then a login after i rebooted (skipping the reboot part, meh)

Usually if you have a completely random reset like that it's a hardware issue like heat or memory.