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On Wed, Nov 07 2012, Domas Monkus wrote:

> 1. How should pollster-specific polling intervals be specified? The
> blueprint mentions that publishers (I assume it means collectors) should
> specify the intervals, however I don't think that a communication channel
> between the collector and the central agent running the pollsters is in
> place.

I did mean publisher, as in we have already a publisher publishing to
ceilometer-collector. Later, we'll have a publisher publishing to, let's
say, a CloudWatch implementation.
So each publisher can specify the frequency of each events it cares
about.

> 2. Should pollsters be able to specify a polling interval (perhaps an
> inherited default) to the central agent?

I'd say no, let's say each publisher set a default frequency.

> 3. If other ways of setting the polling intervals are probably possible
> (e.g. the config file), should there be a hierarchy specified of which
> setting override which ones?

Yes, a simple rule/policy system would make sens like:

collector {
  disk.io: 300,
  instance: 60,
  *: 600,
}

cloudwatch {
  cputime: 300,
  *: 0,
}

would mean the ceilometor-collector publisher would require disk.io
counters every 5 minutes, instance every minute, and the reset every 10
minutes.

Whereas cloudwatch publisher only cares about the cputime every 5
minutes, and don't want the rest.

> 4. Should the current periodic_interval configuration value be used as a
> safe fall back for pollsters without explicitly defined values?

If not required by a publisher, not loaded, no interval. :)

> 5. What is the granularity of polling intervals? Seconds?

Yes.

-- 
Julien Danjou
# Free Software hacker & freelance
# http://julien.danjou.info
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