I have some custom munin graphs that measure an aspect of our sales in our webapp. So I measure "Number of sales so far today". The graph goes up and then reset to 0 at midnight. This is what I want. It works well for the "by day", 5 minute one. Munin by default makes 3 extra graphs showing a longer term view, it has a "by week", "by month" and "by year" view which is based (AFAIK) on the combined data.
However the default seems to be an average of the values, so the total number of sales for a day is an average. I'd much much rather if the combined weekly/monthly/yearly data is based on the maximum/largest for that period. So rather than averaging, it'll 'maximise'?
I'd prefer if this can be done without losing our existing data, however I'm willing to lose the existing data/graphs if that's what's needed.
Best Answer
I would love to know this answer too.
I suspect it would be useful to review what RRDTool can do (this looks possibly useful: http://www.vandenbogaerdt.nl/rrdtool/total.php ) and then hack munin? Or perhaps the CDEF function will let you do this: http://munin-monitoring.org/wiki/fieldname.cdef has some useful info and a link to a tutorial.
You could also try asking your question on the munin-users mailing list. I looked through the plugin exchange and didn't see anything that seemed appropriate.