Hi Martins,
----- Original Message -----
> Hi,
>
> I am starting to work on a ganglia to PCP archive converter as
> highlighted here:
>
> http://oss.sgi.com/bugzilla/show_bug.cgi?id=1078
>
> Since rrd and pcp both have a perl api, the conversion is pretty
> straightforward. The one issue might be that the rrd files are already
> rate converted or averaged or whatever you want to call it. So for what
> PCP would consider counter metrics (network packets, bytes transferred,
> etc) ganglia gives you only the change between sampling intervals, not
> the raw counter value. This is not a problem when constructing an
> archive from existing ganglia files at a single point in time since you
> can accumulate the counter values,
Even here (but also in your later scenarios) it would be fine to export
these values as instantaneous metrics instead of counters, provided the
units are handled correctly. See the sar2pcp perl script for example -
it has to deal with this same situation (everything's already been rate
converted by sadf) - it uses only PM_SEM_INSTANT and PM_SEM_DISCRETE.
cheers.
--
Nathan
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