PERFORMANCE RELATED RELIABILITY MEASURES FOR COMPUTING SYSTEMS

We have developed measures which combine b o t h t h e r e l i a b i l i t y and t h e performance c h a r a c t e r i s t i c s o f comp u t i n g systems. These measures a r e p a r t i c u l a r l y u s e f u l i n comparing t r a d i t i o n a l computer a r c h i t e c t u r e s , such as un ip rocessors and standby redundant systems, w i t h g r a c e f u l l y degrad ing systems. Mu1 t i p r o c e s s o r s and d i s tri buted systems a r e examples o f g r a c e f u l l y degrad ing systems which r e a c t t o a d e t e c t e d f a i l u r e by r e c o n f i g u r i n g t o a s t a t e w i t h a decreased l e v e l o f performance.