CPU cores saturated by OMP code (with 2017 Update 3)

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CPU cores saturated by OMP code (with 2017 Update 3)

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We find that some CPU cores running OMP code are saturated ever since we migrated to Studio 2017 Update 3. The code involving

kmp_set_blocktime(0), "omp parallel sections", "omp parallel for"

was running fine with Studio 2016.

With 2017, calling

kmp_set_library_throughput(); kmp_set_blocktime(0)

does not avoid the saturation. However calling

kmp_set_defaults("KMP_BLOCKTIME=0")

kmp_set_defaults("OMP_WAIT_POLICY=PASSIVE")

avoids it.

Can anyone explain what is going wrong? Is this a bug in 2017?

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