----- Original Message -----
> On 03/08/2016 11:14 AM, Nathan Scott wrote:
> > Hi Mark,
> >
> > ----- Original Message -----
> >> RFC - ship a global derived metrics config directory in the pcp package.
> >> $PCP_VAR_DIR/config/derived along with a config for IOSTAT metrics. Other
> >> configs can be added.
> >
> > My initial concern is: this is putting server-platform-specific stuff on
> > a client-side install - which is kinda going back to the bad old days of
> > agent Installs on client machines.
>
> derived metrics are client-side. I guess we could add them to pmcd,
> server-side,
Yep, understood; I was really just thinking out loud, not suggesting we go
do any of these things - lets work with what we've got for now & reassess
once we have more real-world experience with using it.
> > IOW, your example there (the iostat
> > metrics) is very Linux-specific.
>
> the iostat example is fairly Linux specific. We could add some 'probe' syntax
> to pmLoadDerivedConfig(3), like pmlogconf-setup, but that's not going to
*nod* - feels like overkill at this stage.
> > But, I don't really see any sensible way around it - we need 'em for the
> > archive case, and there's no server-side derived metric concept either,
> > by design IIRC (too complex to do in pmcd I'm sure).
>
> yep
>
> > Sounds like a libpcp API will be needed here? Oh, or maybe not - we could
> > do this in the pmGetOptions code (maybe __pmEndOptions) and that will be
> > visible in all tools without changes then.
>
> somewhere around there. Or actually, anywhere before contexts are created.
> The easiest is just to putenv(PCP_DERIVED_CONFIG=...) if it's not already
> defined, and __dminit() will pick it up in due course. If the probe fails
Yep, good call - so probably no API additions needed, which is good. Watch
out for QA fallout here, special QA handling for the event.* metrics ended up
splattered across the QA universe when we added those two metrics in.
> >
> > Hmm, I wonder if thats the best place or should it be the pcp-conf package?
> > (for a pcp-libs -only install, which someone might do to support just their
> > own PMAPI utility)
>
> yeah guess so. It's needed by all clients, and they require pcp-libs, which
> in turn requires pcp-conf (at least in RPM spec, not sure about deb).
deb has a pcp-conf underlying everything too - see debian/pcp-conf.* files.
cheers.
--
Nathan
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