On the third side

I have more than once found a Munin multi graph set being rendered unreadable by single graph peaking 100 times over the rest of the graphs in the set. The classical example is the Linux (over)committed memory graph on a system leaking memory, peaking in the 100GB area, making the other system memory graphs that are playing along about 1-4GB almost invisible:

One could of course put a hard limit in the RRD file, in my example, at the pysical memory in the machine in question, but this means that I loose oversight by hiding what’s probably a problem. A better solution is to split the graph out, that is, prevent it from graphing in the common memory set, and put it in custom graph. Consider the following munin.conf snipplet:


[my.server.tld]
address my.server.tld
memory.committed.graph no

memory_committed.graph_title Committed Memory
memory_committed.update no
memory_committed.graph_category system
memory_committed.graph_order \
memory=my.server.tld:memory.committed


This produces the following graphs:

Problem solved.

This entry was posted on Monday, April 7th, 2008 at 12:56 pm and is filed under comp, munin, sysadmin. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.