In order to help corroborate whether a Prometheus instance has
flapped until meta-monitoring is in-place, we ought to provide the
instance's start time in the console to aid in diagnostics.
This commit introduces three background compactors, which compact
sparse samples together.
1. Older than five minutes is grouped together into chunks of 50 every 30
minutes.
2. Older than 60 minutes is grouped together into chunks of 250 every 50
minutes.
3. Older than one day is grouped together into chunks of 5000 every 70
minutes.
To achieve that, this PR
- converts static/index.html ("console") and graph to templates
- moved the handlebars template to separated file to avoid escaping issues
Route changes:
/status -> /
/static -> /console
/static/graph.html -> /graph
This roughly comprises the following changes:
- index target pools by job instead of scrape interval
- make targets within a pool exchangable while preserving existing
health state for targets
- allow exchanging targets via HTTP API (PUT)
- show target lists in /status (experimental, for own debug use)