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Scientific libraries designed for Power architecture included in the XL compiler package,
> module load essl
ESSL includes blas lapack and fftw ( but not scalapack). Unfortunately the lapacks included are not complete, so if you need lapack or scalapack you need to add the flag:
-lessl: single-threaded routines
-lesslsmp: multi-threaded routines
The correct wayis to link essl before lapacks, for example:
-L $ {ESSL_LIB} -lesslsmp -L {LIB_LAPACK} -llapack
Other option is ti use the openBLAS (instead of lapack and BLAS) and in some case they are more efficient.
Documentation: https://www.ibm.com/support/knowledgecenter/SSFHY8/essl_content.html
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