Reduce space use spike after sync

[asdacap]

• Reduce aggressiveness of HeavyWrite tune. Reduce target l0 size from 4GB to 2Gb.
• Set max compaction size to 4GB.
• Set kOldestLargestSeqFirst compaction priority for db that uses block number. This significantly reduce write amp.
• Add CompressibilityHint param to account for suprisingly large difference in memtable and sst size. This reduce write amp on first level due to different in size between l0 and l1.

Types of changes

What types of changes does your code introduce?

• Optimization

Testing

Requires testing

• Yes
• No

If yes, did you write tests?

• Yes
• No

Notes on testing

• Looks fine.