Virtual Time III, Part 3: Throttling and Message Cancellation
- Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
This is Part 3 of a trio of papers that unify in a natural way the two historically distinct parallel discrete event synchronization paradigms, optimistic and conservative, combining the best properties of both into a single framework called Unified Virtual Time (UVT). In this part, we survey the synchronization effects that can be achieved by restricting to corner cases the relationships permitted among the control variables, GVT, CVT, TVT, and LVT, which were defined in Part 1. Here we also survey various throttling policies from the literature and describe how they can be implemented in UVT by controlling the value of TVT, including policies that can take advantage of rollback in addition to LP blocking. A significant result is a new category of efficient and higher precision throttling algorithms for optimistic execution that are based on optimistic lookahead, defined in a way that is symmetric to what we now call the conservative lookahead information that is traditionally used for conservative synchronization. Finally, we present a novel algorithm allowing the choice between lazy and aggressive cancellation to be made on a message-by-message basis using either external logic expressed in the model code, or policy code internal to the simulator, or a mixture of both.
- Research Organization:
- Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
- Sponsoring Organization:
- USDOE National Nuclear Security Administration (NNSA)
- Grant/Contract Number:
- AC52-07NA27344
- OSTI ID:
- 2461677
- Report Number(s):
- LLNL--JRNL-819169; 1028026
- Journal Information:
- ACM Transactions on Modeling and Computer Simulation, Journal Name: ACM Transactions on Modeling and Computer Simulation Journal Issue: 4 Vol. 34; ISSN 1049-3301
- Publisher:
- Association for Computing MachineryCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Analysing Probabilistically Constrained Optimism
|
conference | January 2006 |
Limiting Optimism: Time or Event Count?
|
conference | January 2006 |
Distributed Simulation: A Case Study in Design and Verification of Distributed Programs
|
journal | September 1979 |
A study of time warp rollback mechanisms
|
journal | January 1991 |
Optimal memory management for time warp parallel simulation
|
journal | October 1991 |
The local Time Warp approach to parallel simulation
|
conference | July 1993 |
Time Warp simulation in time constrained systems
|
journal | July 1993 |
Understanding supercritical speedup
|
conference | July 1994 |
NPSI adaptive synchronization algorithms for PDES
|
conference | January 1995 |
Adaptive protocols for parallel discrete event simulation
|
conference | January 1996 |
Speculative parallel simulation with an adaptive throttle scheme
|
conference | June 1997 |
Virtual Time III, Part 1: Unified Virtual Time Synchronization for Parallel Discrete Event Simulation
|
journal | October 2022 |
Virtual Time III, Part 2: Combining Conservative and Optimistic Synchronization
|
journal | October 2022 |
Virtual time
|
journal | July 1985 |
Throttled Lazy Cancellation in Time Warp Parallel Simulation
|
journal | February 2008 |
Similar Records
Virtual Time III, Part 2: Combining Conservative and Optimistic Synchronization
Discrete Event Execution with One-Sided and Two-Sided GVT Algorithms on 216,000 Processor Cores