What is pyroscope compaction_level in metrics ?

[julienvey]

Hey 👋

I'm running pyroscope with the default block_ranges 1h0m0s,2h0m0s,8h0m0s. While looking at the compactor metrics, for instance pyroscope_compactions_current, I see there are multiple compactions happening at different "levels".

I see compaction_level with values of 2, 3, 4 and 5. As I only have 3 block ranges, I wonder what those values mean. I was expecting at most 3 compaction levels.