Avoid checksumming exhaust responses twice on the hot replication path

SERVER-132659 Async replication compression pipeline: remove the single-thread compression bottleneck for large-document replication throughput

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• Open

SERVER-131871 Optimize multi-field updates on wide documents: avoid repeated linear child lookups in UpdateObjectNode

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• Closed

SERVER-32156 Linear field lookup in update subsystem can lead to an individual update having quadratic time complexity

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• Needs Scheduling

SERVER-132800 Support configurable multi-threaded oplog writes on secondaries (oplogWriterThreadCount)

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• Backlog