Is it possible to load multiple RRD files and create a single graph with data from all of them? I'm aware of the RRDFileSum class, but I don't want to simply sum the values up, but rather do a subtraction (or even simply plot all the different values in one graph).
Background is that I want to use the memory statistics RRDs created by collectd to draw a single "memory used" graph, but I need to plot a value that consists of "memory used - cached - buffers", and all those values are in different RRD files.
TIA
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Hi,
Is it possible to load multiple RRD files and create a single graph with data from all of them? I'm aware of the RRDFileSum class, but I don't want to simply sum the values up, but rather do a subtraction (or even simply plot all the different values in one graph).
Background is that I want to use the memory statistics RRDs created by collectd to draw a single "memory used" graph, but I need to plot a value that consists of "memory used - cached - buffers", and all those values are in different RRD files.
TIA
First of all… sorry for the late reply.
I just now noticed it.
But, yes, it is possible.
You just need to use the RRDFlotMatrix.
Igor
As far as I can see RRDFlotMatrix stacks the graphs. Is there a way to avoid this? I just want plain temperature graphs.
Not out of the box.
The only two functions are stacking (RRDFlotMatrix) and summing (RRDFileSum).
Sorry,
Igor