A Method for Bounding the E ect of DMA I / O Interference onProgram Execution
نویسندگان
چکیده
A DMA controller that operates in cycle-stealing mode transfers data by \stealing" bus cycles from an executing program. This cycle stealing operation retards the progress of the executing program and extends its execution time. In this paper we rst present a method that bounds the worst-case execution time of a program executing concurrently with a cycle-stealing DMA I/O operation in the simple case where the execution time of each machine instruction is xed. We next extend this method to deal with the case of instruction-cache architectures. We demonstrate the eeectiveness of our methods by the results of simulations of several programs.
منابع مشابه
Bounding DMA Interference on Hard-Real-Time Embedded Systems
A DMA controller that operates in the cycle-stealing mode transfers data by stealing bus cycles from the CPU. The concurrent contention for the I/O bus by a CPU task and a cycle-stealing DMA I/O task retards their progress and extends their execution times. In this paper we first describe a method for bounding the worst-case execution time (WCET) of a CPU task when cycle-stealing DMA I/O is pre...
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