Accession Number : ADA189832

Title :   Performability Modeling Based on Real Data: A Case Study.

Descriptive Note : Technical rept.,

Corporate Author : ILLINOIS UNIV AT URBANA COMPUTER SYSTEMS GROUP

Personal Author(s) : Hsueh, M C ; Iyer, R K ; Trivedi, K S

PDF Url : ADA189832

Report Date : Dec 1987

Pagination or Media Count : 24

Abstract : This paper describes a measurement-based performability model based on error and resource usage data collected on a multi-processor system. A method for identifying the model structure is introduced and resulting model is validated against real data. Model development from the collection of raw data to the estimation of the expected reward is described. Both normal and error behavior of the system are characterized. The measured data show that the holding times in key operational and error states are not simple exponentials and that a semi-Markov process is necessary to model the system behavior. A reward function, based on the service rate and error rate in each state, is then defined in order to estimate the performability of the system and to depict the cost of different types of errors. Keywords: Computer modeling, Computer systems, Risk assessment, Predictability, Errors, Workload, Measurements, Semi-Markov, Performability, Work measurement.

Descriptors :   *DATA PROCESSING, BEHAVIOR, COMPUTERIZED SIMULATION, COMPUTERS, COSTS, ERRORS, ESTIMATES, EXPONENTIAL FUNCTIONS, MARKOV PROCESSES, MODELS, MULTIPROCESSORS, RATES, RISK, WORKLOAD, RESOURCES, UTILIZATION, RECOVERY, PERFORMANCE(ENGINEERING), MATHEMATICAL MODELS

Subject Categories : Computer Systems

Distribution Statement : APPROVED FOR PUBLIC RELEASE