Memory Health/Occupation Linux Machines: cached memory is not considered free/available

[zxyz]

In LibreNMS unter Health - Memory the Physical Memory and Virtual Memory all my Linux VMs Memory is marked red, due to a very high occupation. The VM named monitor below shows the following output:

monitor Physical memory 7.650GB / 7.800GB 151.520MB 98%
monitor Virtual memory 7.650GB / 7.800GB 151.520MB 98%

This is correct, when buffered and cached memory is regarded as occupied.

free -h on monitor shows:

total used free shared buff/cache available
Mem: 7.8G 1.8G 152M 86M 5.9G 5.6G

So actually, monitor is quite happy with its memory. I would suggest to no use the free value but the available value for indication (on Linux machines).

Thanks for LibreNMS!

(latest LibreNMS, ubuntu 16.04)

[laf]

Most likely a duplicate of #3179 please read it and see

[zxyz]

oh, yes it is a dupicate. It flipped through my search. sry for that.

[laf]

The other issue is closed as well. Does it answer your question as we've not changed how we do memory graphs since then afaik

[zxyz]

@laf thanks for asking. It answered my question.
I see the point of @paulgear regarding the use of snmp data.

Unfortunately there is no available memory (as in free -h) value in the Detailed Memory Usage graph (probably beacuse this is not provided by snmp) which would imho be a much better reference as the free value. While available might be "wrong" in some cases regarding system health/alerting, free ist "wrong" in this way most of the times (at least for machines which don't have heaps of memory).

[lock]

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