Fault Tolerance on Symmetric Multiprocessor Machines

 Last reviewed: May 6, 1997
Article ID: Q93597
The information in this article applies to:
  • Microsoft Windows NT operating system version 3.1

A symmetric multiprocessor (SMP) machine is designed to provide fault tolerance. If one processor fails, the SMP machine continues processing threads and keeps the system going using operative processors. Windows NT supports SMP platforms to increase processor power, not for fault tolerance. If a processor fails, Windows NT stops responding ("hangs"). This is not due to a flaw in Windows NT but in the hardware support on 80x86-based SMP machines. At this time, no 80x86-based SMP machine provides the hardware support to recover from a failed processor.

The reliability of a multiprocessor (MP) machine compared to a uniprocessor (UP) machine is difficult to determine. Although a single processor failure can bring the system down, processor failures are rare. The benefit of several times the processing power most likely outweighs the cost of possible system failure.

Additional query words: prodnt
Keywords : kbother ntfault
Version : 3.1
Platform : WINDOWS

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Last reviewed: May 6, 1997
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