Thomas A. Gregg

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Fault tolerance in IBM S/390 systems during the 1980s and 1990s had three distinct phases, each characterized by a different uptime improvement rate. Early TCM-technology mainframes delivered excellent data integrity, instantaneous error detection, and positive fault isolation, but had limited on-line repair. Later TCM mainframes introduced capabilities for(More)
IJ ecent trends in high-end generalpurpose computing point to a need to consolidate commercial informationprocessing applications and ddtabases. Although this need appears to run contraq to the continuing growth of distributed computing. the commercial world has compelling reasons for consolidating data centers and ultimately conputers. These reasons(More)
The IBM eServer z900 introduces new Parallel Sysplex coupling channels that satisfy evolving requirements in a way that minimizes product and development costs. Their design also provides backward compatibility with earlier S/390 models, spans all three coupling channel design points, and anticipates future end-of-life technology issues. The original(More)
I/O subsystem E. W. Chencinski M. A. Check C. DeCusatis H. Deng M. Grassi T. A. Gregg M. M. Helms A. D. Koenig L. Mohr K. Pandey T. Schlipf T. Schober H. Ulrich C. R. Walters The performance, reliability, and functionality of a large server are greatly influenced by the design characteristics of its I/O subsystem. The critical components of the IBM System(More)