4 ms·

Does Munin itself use up a lot of resources? I am curious to try it out

pritambarhate 6y ago
In my experience it's pretty lightweight. But never properly measured its impact. Just didn't notice any big impact to pay attention to it.
justinsaccount 6y ago
It execs scripts for each metric and stores the data using rrdtool. If you are only collecting a few metrics and use a 5 minute collection interval it's probably fine. A while ago I switched from munin to prometheus+node_exporter and with that went from collecting metrics every 5 minutes to more metrics every 15 seconds. Munin is easy to operate initially. You can go from a script that outputs a number to a graph on your screen in a few minutes. It does get more complicated when you want to do something like graph the aggregate of a metric across a subset of machines. It is doable in the configuration, but a hell of a lot harder than just adding a widget in grafana and writing a simple promql query.
Jiejeing 6y ago
Munin is fairly light, but metrics are collected through running various scripts, which is generally more resource-intensive than the usual node-exporter(-like) daemons, so the frequency at which data is updated is usually much lower.
progval 6y ago
I have a munin-master running on an Atom C2338 (very low-end), which monitors about 20 hosts. The whole system uses about 300MB RAM and 40% of a CPU core. It's a little intensive because it recomputes half the images every 5 min, when the cron runs (that's configurable). In terms of disk, munin uses 750MB, and it's not growing thanks to rrdtools; and it writes 1MB/s on average. Bandwidth usage is 5Mb/s on average (to get data from all munin nodes, also every 5 min in my config) Munin nodes themselves are extremely lightweight. Essentially, the master calls the munin-node daemon via a TCP socket, which starts a plugin process and pipes its stdout to the socket. Plugins usually simply call a command like "df" or "netstat", parse its output, and write it in munin's format.
pluc 6y ago
Who monitors the monitorers?!

In my experience it's pretty lightweight. But never properly measured its impact. Just didn't notice any big impact to pay attention to it.

justinsaccount 6y ago

It execs scripts for each metric and stores the data using rrdtool. If you are only collecting a few metrics and use a 5 minute collection interval it's probably fine. A while ago I switched from munin to prometheus+node_exporter and with that went from collecting metrics every 5 minutes to more metrics every 15 seconds. Munin is easy to operate initially. You can go from a script that outputs a number to a graph on your screen in a few minutes. It does get more complicated when you want to do something like graph the aggregate of a metric across a subset of machines. It is doable in the configuration, but a hell of a lot harder than just adding a widget in grafana and writing a simple promql query.

Jiejeing 6y ago

Munin is fairly light, but metrics are collected through running various scripts, which is generally more resource-intensive than the usual node-exporter(-like) daemons, so the frequency at which data is updated is usually much lower.

progval 6y ago

I have a munin-master running on an Atom C2338 (very low-end), which monitors about 20 hosts. The whole system uses about 300MB RAM and 40% of a CPU core. It's a little intensive because it recomputes half the images every 5 min, when the cron runs (that's configurable). In terms of disk, munin uses 750MB, and it's not growing thanks to rrdtools; and it writes 1MB/s on average. Bandwidth usage is 5Mb/s on average (to get data from all munin nodes, also every 5 min in my config) Munin nodes themselves are extremely lightweight. Essentially, the master calls the munin-node daemon via a TCP socket, which starts a plugin process and pipes its stdout to the socket. Plugins usually simply call a command like "df" or "netstat", parse its output, and write it in munin's format.

pluc 6y ago

Who monitors the monitorers?!