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| <a name="GOMP_005fSPINCOUNT-_002d_002d-Set-the-busy_002dwait-spin-count"></a> |
| <h3 class="section">3.16 <code>GOMP_SPINCOUNT</code> – Set the busy-wait spin count</h3> |
| <a name="index-Environment-Variable-15"></a> |
| <a name="index-Implementation-specific-setting-4"></a> |
| <dl compact="compact"> |
| <dt><em>Description</em>:</dt> |
| <dd><p>Determines how long a threads waits actively with consuming CPU power |
| before waiting passively without consuming CPU power. The value may be |
| either <code>INFINITE</code>, <code>INFINITY</code> to always wait actively or an |
| integer which gives the number of spins of the busy-wait loop. The |
| integer may optionally be followed by the following suffixes acting |
| as multiplication factors: <code>k</code> (kilo, thousand), <code>M</code> (mega, |
| million), <code>G</code> (giga, billion), or <code>T</code> (tera, trillion). |
| If undefined, 0 is used when <code>OMP_WAIT_POLICY</code> is <code>PASSIVE</code>, |
| 300,000 is used when <code>OMP_WAIT_POLICY</code> is undefined and |
| 30 billion is used when <code>OMP_WAIT_POLICY</code> is <code>ACTIVE</code>. |
| If there are more OpenMP threads than available CPUs, 1000 and 100 |
| spins are used for <code>OMP_WAIT_POLICY</code> being <code>ACTIVE</code> or |
| undefined, respectively; unless the <code>GOMP_SPINCOUNT</code> is lower |
| or <code>OMP_WAIT_POLICY</code> is <code>PASSIVE</code>. |
| </p> |
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| <dt><em>See also</em>:</dt> |
| <dd><p><a href="OMP_005fWAIT_005fPOLICY.html#OMP_005fWAIT_005fPOLICY">OMP_WAIT_POLICY</a> |
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