Techdocs Library > Flashes > Asynchronous DB2 data sharing locks not counted

Document Author:	Judy Ruby-Brown		Document ID:	FLASH10632
Doc. Organization:	Advanced Technical Support		Document Revised:	02/19/2008
Product(s) covered:	DB2 for z/OS and OS/390; Parallel Sysplex; Tivoli OMEGAMON XE for DB2 on z/OS; Tivoli OMEGAMON XE for DB2 Performance Expert on z/OS; Tivoli OMEGAMON XE for DB2 Performance Monitor on z/OS; z/OS

Abstract: In current versions of DB2 for z/OS, DB2 performance monitors may calculate data sharing global lock contention rates incorrectly if those locks are converted from synchronous requests and are granted asynchronously. Customers likely to encounter this situation have any of these conditions: 1. A coupling facility (CF) is separated from the requesting z/OS image by distance 2. Technology mismatch between requesting z/OS image and the CF with the DB2 lock structure (example: System z9 image with z990//z900 CF) 3. Matched technology between z/OS requester and CF, but slow links (or over committed links) This flash helps you determine if you have this situation and how you can better determine your global locking rate. Read this flash if you have any of the above conditions.

Classification:	Software	Category:	Performance
Platform(s):	IBM System z Family	S/W Pillar(s):	Information Management; Tivoli; System z
O/S:	z/OS	Keywords:	heuristic, XES, links, DB2, Statistics report, data sharing locking, parallel sysplex, z/OS, XCFAS, IRLM