Thanks for the feedback guys...
----- Original Message -----
> I was digging into the Parfait code on the train journey home (hope I don't
> miss my stop) and wondering whether a newer version of Parfait might just
> _always_ [write] identifiers in the new place. If it's going to have to be
> changed to mark it's support for the new v2 version flag, it may as well
> just encode all identifiers in the one spot. The reader of this (pmdammv)
> can just do the heavy lifting identifying when to convert or not.
>
The scenario I'd be concerned about is the old-PCP-new-Parfait combo - it can
take people a long time to upgrade PCP sometimes (*cough*), and if Parfait is
only writing v2 format files then a new Parfait would silently stop working
for existing PCP installations when it needn't, really.
I'm thinking also of punters using parfait-agent. It'd be good if any old PCP
continued to work for them (no requirement for long metric/instance names in
that case) in particular, since they might well be just trying PCP out for the
first time.
Since v2 is so very similar to v1, I'm hopeful that its not going to be a big
task to make Parfait switch it at runtime (well, that was the hope with just
changing a few specific structures/offsets anyway - that many of the classes,
data structures, etc can remain as-is).
Definitely a new pmdammv will want to handle both forms (its readonly though -
no "conversion" per-se, just supporting both and exposing metrics from either,
simultaneously).
cheers.
--
Nathan
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