Upgrade 0.9.8 to 0.9.9

I was able to point to old 0.9.8 whisper files after upgrading to 0.9.9. Not sure about the aggregationmethod.

If upgrading, make sure to run setup.py with --force. You can use whisper-set-aggregation-method.py to change the aggregationMethod on any existing .wsp files

Yes the whisper format has not changed, and in fact it will never change because it is being replaced by the new ceres database in future versions (whisper support while continue to exist indefinitely as we're adding support for arbitrary database backends).

But back to your question about upgrading, if you have a large (and hence probably important) installation I would suggest testing first just as a good practice. There *should* be no issues, but when you're dealing with a large/important user base all changes should be tested first.

Regarding changing the aggregation method, you can manage this per-metric with the whisper-set-aggregation.py script as Aman mentioned and in fact I would suggest just doing that for now (there is a storage-aggregation.conf file you could setup but its going away) because there are API changes coming for how this gets managed, but the whisper-set-aggregation.py script will always work for whisper files.

Changing status to 'answered' because I forgot to hit 'answer'.