Raspberry Pi Memory Loss

dazza120

@evroom I’m using mmm-SystemStats to view it on the magic mirror, unless this is monitoring the memory wrong?

evroom

@dazza120
This modules uses the free command to determine memory usage.
It does free / total times 100 %.
But free (the value) does not take into account the shared memory, cache and buffers used by the system.
It would be better to use the available value.
This value tells you how much memory is available to start a new application.
See man free for some more details.

Modern Linux is making more and more advanced use of memory and swap techniques, making it more and more difficult to determine certain values.

evroom

@evroom
In node_helper.js you could change line 67.
Change $4 into $7.
Then observe if you see the same behavior.

dazza120

@evroom changed it thanks I’ll continue the test much appreciated

dazza120

@evroom hi it’s still declining but a lot slower, I’ll let it continue and see if the mirror locks up if it reaches 0%

dazza120

@evroom yeah it just died, MagicMirror crashed showing the black screen, when MacicMirror was restarted boom 80% free memory. So now I’ve got watchdog on for hopefully when it crashes it will restart with 80% memory

jsteel715

Have you tried running top or (htop if installed) from a terminal cli to see which process(es) are using up the memory?

evroom

@dazza120

Could you send the output of the following commands, when running more or less normal?

free
swapon -s
vmstat 5 10
top -b -o +%MEM | head -n 22

And the suggested htop command is also nice to look at.
Might need to be installed separately.

dazza120

@evroom restarted the hole thing so memory is good. i have no idea what this other thing is that you and @jsteel715 are talking about lol but here is what you asked for with the code. this is normal operation apart from chromium that is shutdown everytime im not using it

pi@raspberrypi:~ $ free
              total        used        free      shared  buff/cache   available
Mem:        3999788      509844     2834580      197580      655364     3197620
Swap:        102396           0      102396
pi@raspberrypi:~ $ swapon -s
Filename				Type		Size	Used	Priority
/var/swap                              	file    	102396	0	-2
pi@raspberrypi:~ $ vmstat 5 10
procs -----------memory---------- ---swap-- -----io---- -system-- ------cpu-----
 r  b   swpd   free   buff  cache   si   so    bi    bo   in   cs us sy id wa st
 1  0      0 2833448  45296 610956    0    0   867    25  513  852 17  8 69  5  0
 1  0      0 2830796  45304 613168    0    0     0     6  552  626  2  1 97  0  0
 0  0      0 2835100  45312 609128    0    0     0    37  537  615  2  1 97  0  0
 0  0      0 2836716  45320 609156    0    0     0    10  433  483  3  1 96  0  0
 0  0      0 2836220  45320 609132    0    0     0     0  383  410  1  1 98  0  0
 0  0      0 2833132  45328 609768    0    0     0    23  308  329  2  1 96  0  0
 0  0      0 2833684  45328 609136    0    0     0    32  502  528  1  1 98  0  0
 0  0      0 2839432  45328 602188    0    0     1     2 1054 1883  6  4 90  0  0
 0  0      0 2830820  45336 609832    0    0     9    13 1684 2816 18  6 76  0  0
 3  0      0 2825096  45344 615684    0    0     0    11 1597 2651 19  5 76  0  0
pi@raspberrypi:~ $ top -b -o +%MEM | head -n 22
top - 19:50:21 up 6 min,  2 users,  load average: 1.35, 0.78, 0.38
Tasks: 159 total,   1 running, 157 sleeping,   0 stopped,   1 zombie
%Cpu(s):  7.7 us,  3.8 sy,  0.0 ni, 88.5 id,  0.0 wa,  0.0 hi,  0.0 si,  0.0 st
MiB Mem :   3906.0 total,   2774.0 free,    502.4 used,    629.6 buff/cache
MiB Swap:    100.0 total,    100.0 free,      0.0 used.   3131.1 avail Mem 

  PID USER      PR  NI    VIRT    RES    SHR S  %CPU  %MEM     TIME+ COMMAND
 1452 pi        20   0  411492 145144  95428 S   0.0   3.6   0:37.40 chromium-+
  815 pi        20   0  537468 141332  82408 S  10.5   3.5   0:26.66 electron
  905 pi        20   0  356568 114216  62964 S   0.0   2.9   0:13.56 electron
 1155 pi        20   0  473740  99856  80016 S   0.0   2.5   0:11.76 chromium-+
 1484 pi        20   0  336364  74940  56704 S   0.0   1.9   0:02.31 chromium-+
 1201 pi        20   0  318296  74660  56632 S   0.0   1.9   0:18.70 chromium-+
  900 pi        20   0  301448  66488  48860 S   0.0   1.7   0:04.48 electron
  494 root      20   0  151824  52472  37340 S   0.0   1.3   0:38.00 Xorg
 1206 pi        20   0  266728  50416  38620 S   0.0   1.3   0:01.99 chromium-+
  539 pi        20   0  136068  44144  25440 S   0.0   1.1   0:01.74 PM2 v3.5.+
 1535 pi        20   0  286880  39344  31156 S   0.0   1.0   0:00.09 chromium-+
  728 pi        20   0  128372  37932  25488 S   0.0   0.9   0:00.98 npm
 1176 pi        20   0  198328  34484  28812 S   0.0   0.9   0:00.17 chromium-+
  451 root      20   0   58952  33852  17416 S  10.5   0.8   0:28.86 vncserver+
  634 pi        20   0  149252  28832  22788 S   0.0   0.7   0:01.44 lxpanel
pi@raspberrypi:~ $

evroom

Could you repeat this when memory usage has increased substantially?

The chromium processes are taking up quite some memory.
I myself have none running.

Did you get the latest packages?

$ sudo apt-get update
$ sudo apt-get dist-upgrade