State dump for measurements
Batch inserts.

Basic strategy is to batch consecutive inserts together per namespace. Batch gets saved whenever:
- An update or delete is done to the same namespace as the insert
- After streaming (up to) 1000 updates from oplog, time from last batch update is larger than 5 seconds.
- More than a threshold of updates have happened in this namespace.
- Program is exiting.

(Commit contains some junk that needs to be cleaned up)
Measurements were taken here
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