RRAs parameters

[muchozol]

Hello,

I've increased polling frequency to once every 60 seconds and changed default RRA parameters to the following values:

Name Steps Rows Timespan**
Hourly (1 minute Average) 1 86400 3600
Daily (5 Minute Average) 5 600 86400
Weekly (30 Minute Average) 30 700 604800
Monthly (2 Hour Average) 120 775 2678400
Yearly (1 Day Average) 1440 797 33053184

I assumed that since 1 step = 60 seconds, 5 minutes average takes 5 steps, etc. I want to have the possibility to look into 1-minute history for 60 days, that's why I have 86400 rows in the first line.

With those settings, daily DB covers approx. 2 days (600 x 5 minutes), Weekly DB covers approx. 14 days, Monthly DB - approx. 64 days, and Yearly DB - 797 days.

Since Hourly DB has 60 days timespan, do I need Daily/Weekly/Monthly DB? How with those overlapping sets of data does RRDTool choose source of information for particular graphs (daily, weekly, monthly)?

Regards.

[rony]

Do you really need them, no... But the are useful and don't take up that much space to have in the RRDTool file.

I can think of uses for the consolidated data that is the Monthly and Weekly and even the Daily data sets.

[fransh]

Did you get cacti to print an extra graph also ? I am trying to figure out how I can put a "10 minute" graph above using an hourly RRA!

any pointers ?

[gandalf]

Find some docs here, especially in the RRDTools section
Reinhard