Restore Size-Tiered compaction strategy

[marvin-j97]

Tiered compaction strategy (called Universal in RocksDB) was part of V1 and V2, but not V3 as of now, which is a bit of a regression. Reasons being the leveled compaction in V3 scaling much better, and me not caring too much about it.

[leonprietobailo]

Hi @marvin-j97

Can you assign this to me? I would like to work on it as a good first issue.

[marvin-j97]

Hi @marvin-j97

Can you assign this to me? I would like to work on it as a good first issue.

Yes. The old implementation is in the 2.x.x branch, though it's probably not perfect and can't be transferred 1:1.