Fault-tolerant Multiprocessor Research Articles

Performance modeling and measurements of real time multiprocessors with time-shared buses

A closed queueing network model is constructed to address workload effects on computer performance for a highly reliable unibus multiprocessor used in real-time control. The model consists of multiserver nodes and a nonpreemptive priority queue. Use of this model requires partitioning the workload into task classes. The time-average steady-state solution of the queuing model directly produces useful results that are necessary in performance evaluation. The model was experimentally justified with the fault-tolerant multiprocessor located at the NASA AIRLAB. Extensive experiments were performed using a synthetic workload generator to measure directly performance parameters, such as processor idle time, system bus contention and task processing times. These measurements determine values for parameters in the queueing model. Experimental and analytic results are compared, demonstrating the validity of the model. >

Performance modelling of a fault-tolerant real-time multiprocessor using stochastic Petri nets

The fault-tolerant multiprocessor (ftmp) is a bus-based multiprocessor architecture with real-time and fault- tolerance features and is used in critical aerospace applications. A preliminary performance evaluation is of crucial importance in the design of such systems. In this paper, we review stochastic Petri nets (spn) and developspn-based performance models forftmp. These performance models enable efficient computation of important performance measures such as processing power, bus contention, bus utilization, and waiting times.

Fault detection, isolation, and reconfiguration in the fault tolerant multiprocessor

The Fault Tolerant Multiprocessor is a highly reliable computer designed to meet a goal of 10 ~ failures per hour. To a large extent, this level of reliability depends upon the ability to detect and isolate faults rapidly and accurately, purge the faulty module, and dynamically reconfigure the remaining good modules. This paper describes fault detection, isolation, and recovery methodology employed in the Fault Tolerant Multiprocessor. The second part of the paper deals with experimental results obtained by actually injecting faults at the pin level in the Fault Tolerant Multiprocessor. Over 21,000 faults were injected in the central processing unit, memory, bus interface circuits, and error detection, masking, and error reporting circuits of one line replaceable unit of the multiprocessor. Detection, isolation, and reconfiguration times for each fault were recorded. These results were found to be in close agreement with earlier assumptions made in reliability modeling. The experimental results are summarized in this paper.

Correction to "Fault-Tolerant Multiprocessor Link and Bus Architectures"

In the above paper1 the following typographical errors should be corrected.

Design and Evaluation of a Fault-Tolerant Multiprocessor Using Hardware Recovery Blocks

In this paper we consider the design and evaluation of a fault-tolerant multiprocessor with a rollback recovery mechanism.

Rollback propagation detection and performance evaluation of FTMR 2 M—a fault-tolerant multiprocessor

In this paper we consider the rollback propagation and the performance of a fault-tolerant multiprocessor with a rollback recovery mechanism (FTMR 2 M)[1], which was designed to be tolerant of hardware failure with minimum time overhead. Rollback propagation between cooperating processes is usually required to ensure correct recovery from failure. To minimize the waste of processor time and storage overhead required for handling sophisticated rollback propagations, the FTMR 2 M always keeps one recoverable state. Approaches for evaluating the recovery overhead and analyzing the performance of FTMR 2 M are presented. Two methods for detecting rollback propagations and multi-step rollbacks between cooperating processes are also proposed.

FTMP—a highly reliable fault-tolerant multiprocessor for aircraft : Albert L. Hopkins, Jr., T. Basil Smith, III and Jaynarayah H. Lala. Proc. IEEE66, (10) 1221 (October 1978)

FTMP—a highly reliable fault-tolerant multiprocessor for aircraft : Albert L. Hopkins, Jr., T. Basil Smith, III and Jaynarayah H. Lala. Proc. IEEE66, (10) 1221 (October 1978)