The term 'database' in the current documentation is ambiguous

When you run the db.fsyncLock() command, the following happens:

• The command acquires the global write lock, blocking all write operations and all read operations on that node
• The command flushes to disk all of the changes in all of the files used by MongoDB

The global write lock will continue to be held until the command 'db.fsyncUnlock()' is run.