auto_partitioner Class

Summary

Specify that a parallel loop should optimize its range subdivision based on work-stealing events.

Header

#include "tbb/partitioner.h"

Syntax

class auto_partitioner;

Description

A loop template with an auto_partitioner attempts to minimize range splitting while providing ample opportunities for work-stealing.

The range subdivision is initially limited to S subranges, where S is proportional to the number of threads specified by the task_scheduler_init or task_arena. Each of these subranges is not divided further unless it is stolen by an idle thread. If stolen, it is further subdivided to create additional subranges. Thus a loop template with an auto_partitioner creates additional subranges only when necessary to balance load.

Tip

When using auto_partitioner and a blocked_range for a parallel loop, the body may be passed a subrange larger than the blocked_range's grainsize. Therefore do not assume that the grainsize is an upper bound on the size of the subrange. Use a simple_partitioner if an upper bound is required.

Members

namespace tbb {
    class auto_partitioner {
    public:
        auto_partitioner();
        ~auto_partitioner();
    };
}
      
The following table provides additional information on the members of this template class.
Member Description
auto_partitioner()

Construct an auto_partitioner.

~auto_partitioner()

Destroy this auto_partitioner.

For more complete information about compiler optimizations, see our Optimization Notice.