Operating System Considerations in the Multiprocessor MIDAS Environment

The operating system for MIDAS provides interfaces for custom hardware, debugging facilities, and runtime support. The MIDAS architecture uses various specialized hardware devices for controlling the multiple processors and to achieve high I/O throughput. The operating system interfaces with the custom hardware for diagnostics, problem setup, and loading the processors with user code. After the code is loaded, a debugging facility may be used to examine or modify the program in any of the processors, or all the processors simultaneously. During execution of the code, the operating system monitors the processors for exceptional conditions, detects hardware failures, and gathers statistics on performance. This performance information includes histograms depicting instruction execution frequency and analysis of data flow.