SERVER-30111 Mapreduce uses global lock when outputting to empty collection

• 
• Closed

SERVER-6892 Convert GlobalWrite to db lock in mr.cpp

• 
• Closed

SERVER-13449 Possible to prevent global lock during map reduce?

• 
• Closed

SERVER-13442 mapReduce nonAtomic output option

• 
• Closed

DOCS-3286 Map/reduce documentation is wrong about write lock

• 
• Closed