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> > > Do we need to protect against having the polling performed
> > > too frequently and consuming too many resources on the
> > > server?
> >
> >
> > So the idea is to mitigate this by sharing polling cycles where
> > possible.
> >
> > Say the metering publisher needs to sample every 10 minutes,
> > whereas a metrics publisher needs a more fine-grain, say
> > every 2 minutes. In that case, the yield from every fifth
> > polling cycle will be shared and published by both.
> 
>
> Sure, that makes sense. What do we do if the user configures a
> pollster to run every 10 seconds


That's a good question, and I guess there are a couple broad
approaches we could take.

1. Give the user enough rope to hang themselves if they so choose,
   but also enough guidance in docco etc. to hopefully ensure that
   the deligent user does not fall into the trap of configuring
   too high a polling frequency. I guess that is kind of what we
   are doing right now, though with a global (periodic_interval)
   config as opposed to one specific to each per-publisher/pollster
   pair.

2. Impose good behavior on the recalcitrant user by enforcing
   sanity limits on the frequency of polling configured. So for
   example we could insist that the period is taken from an
   "approved" list (say 1 min, 5 min, 10 min, 1 hour, 12 hour
   etc.) or round up any sub-minute periods to the next highest
   minute. In that case, a once-per-10s frequency would either be
   rejected outright or rounded up to a more sane 60s.

Cheers,
Eoghan