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This study evaluates the performance of various probabilistic model checkers with a focus on tool selection. Four examples are presented along with an overall evaluation of the tools based on selected benchmarks. The experiments cover qualitative properties, bounded reachability, steady-state properties, and nested formulas, showcasing the tools' capabilities and limitations. The analysis considers timing, memory usage, and simulation accuracy, providing insights for potential users in fields like distributed systems, security, biology, and quantum computing.
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How Fast and Fat IsYour Probabilistic Model Checker? an experimental performance comparison David N. Jansen3,1, Joost-Pieter Katoen1,2, Marcel Oldenkamp2,Mariëlle Stoelinga2, Ivan Zapreev1,2 1 MOVES Group, RWTH Aachen University 2 FMT Group, University of Twente, Enschede 3 ICIS, Radboud University, Nijmegen
ProbabilisticModel Checking Probabilistic System Probabilistic Requirement PRISM (hybrid) PRISM (sparse) MRMC VESTA ETMCC Probabilistic Model Probabilistic Formula YMER ≤ Probabilistic Model Checker Yes No Probability
Why This Work? • Used more often • applications: distributed systems, security, biology, quantum computing... • Powerful tools • Problem: Which tool to choose?
ProbabilisticModel Checkers Probabilistic System Probabilistic Requirement Choices made Four examples Probabilistic Model Probabilistic Formula Overall evaluation Probabilistic Model Checker Yes No Probability
Experiment Relevance • Repeatable • Verifiable • Significant • Encapsulated
SynchronousLeader Election • nodes in a ring elect a leader • each node selects random number as id • passes it around the ring (synchronously) • if unique id,node with maximum unique id is leader • [Itai & Rodeh, 1990]
1 4 2 2 5 3 1 5 SynchronousLeader Election
1 4 4 5 1 5 2 5 1 4 5 1 2 2 1 1 3 5 3 5 2 2 2 3 SynchronousLeader Election 1 4 2 2 5 3 1 5
RandomizedDining Philosophers • Dining Philosophers • pick up chopsticks in random order • Deadlocks resolved • if there is no second chopstick,give up eating • [Pnueli & Zuck, 1986]
Birth–Death Process • Models a waiting queue • Standard modelin performance evaluation • Limit queue size to get finite model
Tandem Queueing Network • Two queues after each other • [Hermanns, Meyer-Kayser & Siegle, 1999] checkin counter two-phase security check exponential
Cyclic Polling System • server cycles over n stationsand serves each one in turn • e.g. teacher walks through class,each pupil may ask a question • [Ibe & Trivedi, 1990]
Modelling informal description PRISM model adapt syntax VESTA model .tra format model YMER model ETMCC MRMC PRISM YMER VESTA
Experiment 1Qualitative Properties • unbounded reachability with prob 1 • Cyclic Polling System: busy1P≥1(trueUpoll1)If station 1 is busy,the server will poll it eventually
PRISM: MTBDD Size • Multi-Terminal BDD =data structure for transition matrix • size heavily depends on model • large MTBDD slow
CPS versus SLE runtime 458.847 states 1.131.806 MTBDD nodes 7.077.888 states 2.745 MTBDD nodes
VESTA:simulation problem • actual probability close to bound P≥p(...) • estimate is almost always in [p–,p+] • some irregularity stops the simulation • 0.95 Prob(yes actual Prob≥p) Prob(actual Prob≥p yes)
Result Overview: Timing depends heavily on MTBDD size depends heavily on MTBDD size depends heavily on MTBDD size
Result Overview: Memory MTBDD size varies heavily almost independent from model size
Experiment 2Bounded Reachability • Tandem Queueing Network:P<0.01(trueU ≤2full)Is the probabilitythat the system gets full in 2 time unitssmall?
Experiment 3Steady State Property • Tandem Queuing NetworkS>0.2( P>0.1(X2nd queue full) )In equilibrium,the probability to satisfy is > 0.2 P>0.1(X2nd queue full) P>0.1(X ...)
Simulating Steady State? • simulation of bounded reachabilityhas clear stopping criterion • simulation of unbounded reachability reachability with very large bound • simulation of steady state? never stops
Nested Formulas • Birth–Death Process:P≥0.8(P≥0.9(trueU ≤100n70) Un50)The probability to reach n50 (while the probability to reach n70in 100 steps never drops <0.9)is ≥0.8
Result Overview: Timing did not terminate