This is based on my experience while debugging https://github.com/prometheus/prometheus/issues/3943.
I needed to deduct few things, and all that would be just bit easier with these two logs:
- new block's ULID on each compaction.
- actual list of Blocks (ulid + time range) on Prometheus startup (easy to log that while repairing blocks).
We don't really need blocks that takes part in compaction - that can be deducted easily based on time ranges of blocks we have currently in system.
What do you think?
Signed-off-by: Bartek Plotka <bwplotka@gmail.com>