# par-runtime-control, Qpar-runtime-control

Generates code to perform run-time checks for loops that have symbolic loop bounds. This feature is only available for ifort.

## Syntax

Linux: | -par-runtime-control[n] -no-par-runtime-control

macOS: | -par-runtime-control[n] -no-par-runtime-control

Windows: | /Qpar-runtime-control[n] /Qpar-runtime-control-

## Arguments

n | Is a value denoting what kind of runtime checking to perform. Possible values are:
0 | Performs no runtime check based on auto-parallelization. This is the same as specifying -no-par-runtime-control (Linux* and macOS) or /Qpar-runtime-control- (Windows*).
1 | Generates runtime check code under conservative mode. This is the default if you do not specify n.
2 | Generates runtime check code under heuristic mode.
3 | Generates runtime check code under aggressive mode.

## Default

-no-par-runtime-control or /Qpar-runtime-control- | The compiler uses default heuristics when checking loops.

## Description

This option generates code to perform run-time checks for loops that have symbolic loop bounds.

If the granularity of a loop is greater than the parallelization threshold, the loop will be executed in parallel.

If you do not specify this option, the compiler may not parallelize loops with symbolic loop bounds if the compile-time granularity estimation of a loop can not ensure it is beneficial to parallelize the loop.

### Note

This option may behave differently on Intel® microprocessors than on non-Intel microprocessors.

## IDE Equivalent

None

## Alternate Options

None

Parent topic: Offload Compilation, OpenMP*, and Parallel Processing Options