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It resulted in an almost error free ECS system

During the last three months of operation an error report was made for most system crashes. An examination of reports, 18 in all, showed one crash for unknown reasons, three for suspected hardware causes, and the rest identified as high level system errors (disk/directory system or command processor). During this period the system was run for at least 8 hours each working day, with a fairly continuous load of several users. Even if the one unknown and three suspected hardware crashes are attributed to the ECS system, I feel that this represents an excellent record. The system change log for the last six months of operation records 41 system modifications, of which 7 contained changes to the ECS system proper, and 6 contained changes to the I-O drivers. Only 4 of the 7 changes to the ECS system proper were for repairing errors. The others were for adding new features or changing assembly parameters.

Paul McJones