On 23-12-2011 23:59, Ralph Mitchell wrote:
The one day graph *would* look fine, but I kinda like the 3-day.
The "blocky" look I'm seeing comes from RRD generating the graph using the best datasource to fit the size you're asking for. By default, the first data store contains 576 points at 5 minute intervals, which covers 2 days. The second data store contains 576 point at 30 minute intervals, which is 12 days. Each of the 30-minute data points is generated by averaging together 6 of the 5-minute data points. If you ask rrd to generate a 3 day graph, there are not enough points in the first data store, so it uses the second store and each point on the graph then covers more pixels.
It's the same effect as zooming in on a graph. To fix it, I've resized the existing RRDs to hold 864 data points, so there will be enough fine-grain data to get a decent 3-day graph.
Right, forgot to mention that I've done something similar on the www.xymon.com site.
You can change it in "rrddefinitions.cfg", but it will not change any existing files - only newly created ones.
Regards, Henrik