Re: Need help analyzing (kernel?) memory usage and reclaiming RAM (Debian Stretch)

[Peter Wiersig <peter@friesenpeter.de>]

Martin Schwarz <debian-lists@alias.kuroi.de> writes:
> root@rad-m2m-srv02:~# ps aux --sort=-rss | head -15

you're choosing the wrong sort field to debug your problem here:
man ps:
"""
       rss         RSS       resident set size, the non-swapped physical memory that a task has used (in kiloBytes).
                             (alias rssize, rsz).
...
       vsz         VSZ       virtual memory size of the process in KiB (1024-byte units).  Device mappings are currently
                             excluded; this is subject to change. (alias vsize)."""

try the latter field if the problem is repeating.  VSZ can be very
misleading with graphical processes, but that should not occur here.

https://stackoverflow.com/questions/7880784/what-is-rss-and-vsz-in-linux-memory-management

https://stackoverflow.com/a/21049737/2911961
""RSS is the Resident Set Size and is used to show how much memory is
allocated to that process and is in RAM. It does not include memory that
is swapped out. It does include memory from shared libraries as long as
the pages from those libraries are actually in memory. It does include
all stack and heap memory.

VSZ is the Virtual Memory Size. It includes all memory that the process
can access, including memory that is swapped out, memory that is
allocated, but not used, and memory that is from shared libraries.""

Peter