DB2 lock manager
The DB2 internal resource lock manager (IRLM) is both a separate subsystem and an integral component of DB2. Each DB2 subsystem must have its own instance of IRLM. 
IRLM works with DB2 to control access to your data. DB2 requests locks from IRLM to ensure data integrity when applications, utilities, and commands all attempt to access the same data.
Get Official Introduction to DB2® for z/OS®, The, 2nd Edition now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
