https://community.intel.com/t5/Intel-oneAPI-Math-Kernel-Library/MKL-on-a-16-core-Linux-machine/m-p/915554#M12539 I'm having trouble getting MKL 10.0.1 to exploit more than 1 core on a 16 core Xeon machine. Im running gcc 4.1.2 and Linux 2.6.18-53.1.4.el5.<BR /><BR />What I do know:<BR />1. The same code successfully exploits 4 cores on an XP machine<BR />2. Other OpenMP code on the Linux machine successfully exploits all 16 cores.<BR />3. omp_get_num_threads() returns 16.<BR />4. omp_set_num_threads(16) causes a seg fault. (smaller values don't work either)<BR />5. Im the only one on the machine.<BR />6. The BLAS examples that come with MKL also only use 1 core and seg fault when I try omp_set_num_threads().<BR /><BR />I suspect Im linking wrong. Ive tried both static linking:<BR /><BR />MKLLIB = /opt/intel/mkl/10.0.1.014/lib/em64t<BR />LDFLAGS = -L${MKLLIB} -lguide -liomp5 -lmkl lm lpthread<BR /><BR />And dynamic linking:<BR /><BR />MKLLIB = /opt/intel/mkl/10.0.1.014/lib/em64t<BR />LDFLAGS = -L${MKLLIB} ${MKLLIB}/libmkl.so ${MKLLIB}/libiomp5.so -lm lpthread<BR /><BR />Neither makes a difference. Is there something obvious Im missing?<BR /><BR />Any advice would be appreciated,<BR /><BR />Ted<BR /><BR /> Thu, 28 Feb 2008 16:25:42 GMT twkim 2008-02-28T16:25:42Z https://community.intel.com/t5/Intel-oneAPI-Math-Kernel-Library/MKL-on-a-16-core-Linux-machine/m-p/915554#M12539 I'm having trouble getting MKL 10.0.1 to exploit more than 1 core on a 16 core Xeon machine. Im running gcc 4.1.2 and Linux 2.6.18-53.1.4.el5.<BR /><BR />What I do know:<BR />1. The same code successfully exploits 4 cores on an XP machine<BR />2. Other OpenMP code on the Linux machine successfully exploits all 16 cores.<BR />3. omp_get_num_threads() returns 16.<BR />4. omp_set_num_threads(16) causes a seg fault. (smaller values don't work either)<BR />5. Im the only one on the machine.<BR />6. The BLAS examples that come with MKL also only use 1 core and seg fault when I try omp_set_num_threads().<BR /><BR />I suspect Im linking wrong. Ive tried both static linking:<BR /><BR />MKLLIB = /opt/intel/mkl/10.0.1.014/lib/em64t<BR />LDFLAGS = -L${MKLLIB} -lguide -liomp5 -lmkl lm lpthread<BR /><BR />And dynamic linking:<BR /><BR />MKLLIB = /opt/intel/mkl/10.0.1.014/lib/em64t<BR />LDFLAGS = -L${MKLLIB} ${MKLLIB}/libmkl.so ${MKLLIB}/libiomp5.so -lm lpthread<BR /><BR />Neither makes a difference. Is there something obvious Im missing?<BR /><BR />Any advice would be appreciated,<BR /><BR />Ted<BR /><BR /> Thu, 28 Feb 2008 16:25:42 GMT https://community.intel.com/t5/Intel-oneAPI-Math-Kernel-Library/MKL-on-a-16-core-Linux-machine/m-p/915554#M12539 twkim 2008-02-28T16:25:42Z