README.ploticus

Plotting graphs with ploticus
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Ploticus is a simple graphing package

http://ploticus.sourceforge.net/

You can use ploticus in combination with kar to graph pretty much
anything.

You'll need to create an input file. The simplest way is to use the kar
print subcommand and then filter the output with grep. (It would be
nice to think that kar would have sophisticated filtering, but it
doesn't really.)

So, suppose I was interested in writes to disk device sd4. The
following would generate a data file that ploticus could use:

./kar print :::writes | grep sd4:writes > datafile

And then I could use the chron prefab in ploticus to graph that, with
the data=datafile argument. The important thing here is that field 1 is
a time (so you need to tell ploticus that it's a time with the
unittype=time parameter) and the value is in field 3

pl -prefab chron unittype=time title="Writes to sd4" xlbl="Time" ylbl="bytes/s" mode=line data=datafile x=1 y=3