Parallelize

evaluates expr using automatic parallelization.

Details and Options

Parallelize[expr] automatically distributes different parts of the evaluation of expr among different available kernels and processors.
Parallelize[expr] normally gives the same result as evaluating expr, except for side effects during the computation.
Parallelize has attribute HoldFirst, so that expressions are not evaluated before parallelization.
The Method option for Parallelize specifies the parallelization method to use. Possible settings include:

	"CoarsestGrained"	break the computation into as many pieces as there are available kernels
	"FinestGrained"	break the computation into the smallest possible subunits
	"EvaluationsPerKernel"->e	break the computation into at most e pieces per kernel
	"ItemsPerEvaluation"->m	break the computation into evaluations of at most m subunits each
	Automatic	compromise between overhead and load-balancing

Method->"CoarsestGrained" is suitable for computations involving many subunits, all of which take the same amount of time. It minimizes overhead, but does not provide any load balancing.
Method->"FinestGrained" is suitable for computations involving few subunits whose evaluations take different amounts of time. It leads to higher overhead, but maximizes load balancing.
The DistributedContexts option for Parallelize specifies which symbols appearing in expr have their definitions automatically distributed to all available kernels before the computation.
The default value is DistributedContexts:>$Context, which distributes definitions of all symbols in the current context, but does not distribute definitions of symbols from packages.

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Map a function in parallel:

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Generate a table in parallel:

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Functions defined interactively can immediately be used in parallel:

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Introduced in 2008

(7.0)

Updated in 2010

(8.0)

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