Currently, oplog application logic is split over several methods: _multiApply takes a batch of oplog entries and schedules threads to apply them in parallel, applyOplogGroup is the thread worker function which attempts to group inserts and calls applyOplogEntryBatch, which applies a single oplog entry or a group of inserts. While the code path is clear, the names are not. This is due to the ambiguity of terms such as 'batch' and 'group'. Given that batch refers to a set of oplog entries to be apply and group refers to a set of groupedInserts, we can rename the aforementioned methods as follows:

• _multiApply will be renamed _applyOplogBatch.
• applyOplogGroup will be renamed applyOplogBatchPerWorker.
• -applyOplogEntryBatch will be renamed applyOplogEntryOrGroupedInserts.

Additionally, the class OplogEntryBatch will be renamed OplogEntryOrGroupedInserts.