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Global default thread count |
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C Name
CPX_PARAM_THREADS
C++ Name
Threads
Java Name
Threads
.NET Name
Threads
InteractiveOptimizer
threads
Identifier
1067
Description
Sets the default number of parallel threads that will be invoked by any CPLEX parallel optimizer. Settings of this thread parameter interact with settings of the parallel mode parameter (CPX_PARAM_PARALLELMODE
, ParallelMode
) as summarized in Table 1, Table 2, and Table 3.
For single threads, the parallel algorithms behave deterministically, regardless of thread and parallel mode parameter settings; that is, the algorithm proceeds sequentially in a single thread.
In this context, sequential means that the algorithm proceeds step by step, consecutively, in a predictable and repeatable order within a single thread. Deterministic means that repeated solving of the same model with the same parameter settings on the same computing platform will follow exactly the same solution path, yielding the same level of performance and the same values in the solution. Sequential execution is deterministic. In multithreaded computing, a deterministic setting requires synchronization between threads. Opportunistic entails less synchronization between threads and thus may offer better performance at the sacrifice of repeatable, invariant solution paths and values in repeated runs on multiple threads or multiple processors.
In the following tables, maximum number of threads means the minimum of these two values:
Values
Value |
Meaning |
---|---|
0 |
Automatic: let CPLEX decide; default |
1 |
Sequential; single threaded |
N |
Uses N threads; N is limited by license and available processors |
ParallelMode
, CPX_PARAM_PARALLELMODE
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