MongoDB 3.1.8 has been released. As a reminder, 3.1.8 is a development release and is not intended for production use. The 3.1 series will evolve into 3.2, which will be for production.
New/Fixed in This Release:
SERVER-785 Support Filtered (Partial) Indexes
SERVER-2227 Per index access stats
SERVER-12015 Reenable use of covering indexes with aggregation
SERVER-19007 Built-in facility for full-time diagnostic data capture
SERVER-19551 Keep “milestones” against WT oplog to efficiently remove old records
SERVER-19975 30% performance regression on simple insert workload on primary
SERVER-20204 Segmentation fault during index build on 3.0 secondary
As always, please let us know of any issues.