System Monitor showing large amounts of ram usage but not the process.

aDragon · 2016-04-19 22:14:15

System monitor and top show an increasing amount of ram and CPU usage but no processes that are using that much. The amount of ram being used increases until rebooting. Is there any way to tell what is using up the system recources besides top and System Monitor? Sorry if this is the wrong place for this.

V1del · 2016-04-20 00:06:48

Likely to be a case of disk caching - see http://www.linuxatemyram.com/

check the output of free, whatever is in the buffers/cache line is RAM that is used for disk caching but can be immediately given to processes when necessary.

aDragon · 2016-04-20 01:11:03

I am fairly confident that it is not disk cacheing as there is a noticable slow down/freeze whenever it occurs. I will have to check free -m when it occurs to be sure.

Last edited by aDragon (2016-04-20 01:12:42)

DeadMetaler · 2016-04-20 06:47:15

Maybe tmpfs eat your RAM.

Head_on_a_Stick · 2016-04-20 06:50:45

aDragon wrote:

Is there any way to tell what is using up the system recources besides top and System Monitor?

`ps_mem` was added to [Community] recently, try that.

https://www.archlinux.org/packages/comm … ny/ps_mem/

triforce · 2016-04-20 11:22:18

atop is a decent system resources monitor.

I also use this to show the top five memory hungry processes:

ps aux --sort=-%mem | awk 'NR<=5{print $0}'

Another thing to try is watch for processes:

watch ps aux --sort=-%mem

Edited: Typo

Last edited by triforce (2016-04-20 14:37:53)

aDragon · 2016-04-23 06:44:12

aDragon wrote:

I am fairly confident that it is not disk cacheing as there is a noticable slow down/freeze whenever it occurs. I will have to check free -m when it occurs to be sure.

Definetely not cacheing. System monitor counts cached RAM as free.

aDragon · 2016-04-26 21:29:57

"free -m" is showing 1200 used with 6100 buffer/cached. However avalible is only showing 700. I had thought avalible was buff/cache + free but aparently I am wrong.

              total        used        free      shared  buff/cache   available
Mem:           7451        1218          61           3        6171         776
Swap:          7558         116        7442

And "ps aux --sort=-%mem | awk 'NR<=5{print $0}'" isn't showing anything using that much memory.

ps aux --sort=-%mem | awk 'NR<=5{print $0}'
USER       PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
sam       1664 54.8  5.3 1816728 409492 tty2   Sl+  16:29  32:42 firefox
root     27902 86.4  1.7 182100 130076 ?       Ds   17:26   2:07 /usr/lib/systemd/systemd-journald
sam        809  8.5  1.6 1956896 127116 tty2   Sl+  16:28   5:09 /usr/bin/gnome-shell
sam      26962  4.6  1.3 791872 99652 tty2     Sl+  17:23   0:13 cool-retro-term

Last edited by aDragon (2016-04-26 21:32:15)

V1del · 2016-04-26 22:40:25

Yes buff cache is disk cache, very possible that used tmpfs space is counted as such as well. But as mentioned earlier, if you start to start more applications this can be immediately passed on. Are you doing something with a lot of writes? (Well firefox usually does quite a few which will fill up the disk cache)

Also:

man free

available is an estimation of memory available during start of new applications without starting to swap.

You might also want to check the output of df to see if your tmpfs is abnormally full, it should usually be very small usage wise.

Last edited by V1del (2016-04-26 22:46:48)

aDragon · 2016-04-27 03:26:58

tmps doesn't seem to be very high according to df

Filesystem     1K-blocks      Used Available Use% Mounted on                         
dev              3812376         0   3812376   0% /dev                   
run              3815044       776   3814268   1% /run                   
/dev/sda8      455205256 289188416 142870652  67% /                           
tmpfs            3815044     12868   3802176   1% /dev/shm                           
tmpfs            3815044         0   3815044   0% /sys/fs/cgroup                     
tmpfs            3815044        64   3814980   1% /tmp
/dev/sda2         262144     99188    162956  38% /boot
tmpfs             763012        16    762996   1% /run/user/120
tmpfs             763012        52    762960   1% /run/user/1000

I tested not running Firefox and while that seemed to help, it still eventually occurred after a while. So, I am not sure if it was just in my head or not.

However, system journal and kworker seem to be using an fairly large amount of CPU.

ps aux --sort=-%cpu | awk 'NR<=5{print $0}'
USER       PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
root     22616 77.5  1.6 173928 123960 ?       Rs   23:24   0:22 /usr/lib/systemd/systemd-journald
root        92 57.6  0.0      0     0 ?        S    22:33  29:51 [kworker/0:2]
root        38 32.3  0.0      0     0 ?        R    22:33  16:45 [kworker/0:1]

Arch Linux

#1 2016-04-19 22:14:15

System Monitor showing large amounts of ram usage but not the process.

#2 2016-04-20 00:06:48

Re: System Monitor showing large amounts of ram usage but not the process.

#3 2016-04-20 01:11:03

Re: System Monitor showing large amounts of ram usage but not the process.

#4 2016-04-20 06:47:15

Re: System Monitor showing large amounts of ram usage but not the process.

#5 2016-04-20 06:50:45

Re: System Monitor showing large amounts of ram usage but not the process.

#6 2016-04-20 11:22:18

Re: System Monitor showing large amounts of ram usage but not the process.

#7 2016-04-23 06:44:12

Re: System Monitor showing large amounts of ram usage but not the process.

#8 2016-04-26 21:29:57

Re: System Monitor showing large amounts of ram usage but not the process.

#9 2016-04-26 22:40:25

Re: System Monitor showing large amounts of ram usage but not the process.

#10 2016-04-27 03:26:58

Re: System Monitor showing large amounts of ram usage but not the process.

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