DB2's use of the coupling facility for data sharing

We examine the problems encountered in extending DATABASE 2™ (DB2®) for Multiple Virtual Storage/Enterprise Systems Architecture (MVS/ESA™), also called DB2 for OS/390™, an industrial-strength relational database management system originally designed for a single-system environment, to support the multisystem shared-data architecture. The multisystem data sharing function was delivered in DB2 Version 4. DB2 data sharing requires a System/390® Parallel Sysplex™ environment because DB2's use of the coupling facility technology plays a central role in delivering highly efficient and scalable data sharing functions. We call this the shared-data architecture because the coupling facility is a unique feature that it employs.