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Is it possible to use M3 without a retention downsampling policy? For example, to retain timeseries metrics at the 1 second resolution indefinitely for one or two days worth of data.

Edit: I was interested in M3 for this instead of just a time series DB because I’d also like to aggregate the metrics at lower resolutions and higher resolutions.

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Hey, it is yes - by default all metrics are unaggregated, it’s only until you set aggregation and mapping rules that downsampling occurs.

It’s mainly just disk space that is the primary bottleneck.

Oh ok, is it possible to also maintain an aggregated “view” at the same time as an event view?

Yup indeed, we have to make this more friendly because you have to curl an HTTP/JSON endpoint right now to set the configuration (we’ll release an embedded UI for policy rules editing soon, called m3ctl).

Basically though when you set retention mapping rules, metrics are downsampled to whatever resolution you choose (10s, 1min, 10min, etc) and then stored for whatever time the retention the namespace you have setup for that policy.

And with respect to my comment about disk space being the bottleneck - unless you have a huge dataset you actually might not be bottlenecked by disk, it’s just we’ve encountered that at times with our really high cardinality data sets.

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