Steve Thomas of CA Technologies presents a great introduction into the world of locks, latches, claims and drains. A must see for all developers working wit Db2 for z/OS as well as all DBAs wanting to refresh their knowledge.
Starting in Db2 Version 188.8.131.52, a new feature called 'DB2_AVOID_LOCK_ESCALATION' provides control over lock escalation behaviour. The feature is configured through a dynamic (no instance recycling needed) registry variable:
While system failures seldom happen, most customers expect crash recovery to complete quickly. Our development team decided upon a solution which promised increased availability, without risking the distinguished resilience that Db2 has achieved over the decades.
With the many new features introduced in 184.108.40.206, not to be overlooked are some of the enhancements made in the area of Recovery and Availability.
This article by Michael Roecken and David Sciaraffa does a deep dive into the recovery and availability enhancements in Db2 V220.127.116.11