Open Stack

Excerpts from George Shuklin's message of 2015-02-11 17:59:02 -0800:
> Ceilometer is in sad state.
> 
> 1. Collector leaks memory. We ran it on same host with mongo, and it 
> grab 29Gb out of 32, leaving mongo with less than gig memory available.

I wonder how hard it would be to push Ceilometer down the road of being
an OpenStack shim for collectd instead of a full implementation. This
would make the problem above go away, as collectd is written in C and is
well known to be highly optimized for exactly this type of workload.

You would need a more advanced AMQP plugin that understands how to turn
the notifications in OpenStack into collectd values, and then make some
decisions on whether to keep Ceilometer's SQL/MongoDB backend or just
teach Ceilometer to read from the various collectd output formats. I
think the latter will be a bigger win, but the former would be easier
for a more incremental migration.

Anyway, if people are interested in "saving" Ceilometer from being a
bit sluggish, that seems like a good first step in the investigation.