I am struggling with a python reproducibility problem across different machines. I have two machines: an older server with SSE4_2 and a newer desktop with AVX. Running the same python script on both machines results in different outputs (I made sure both virtualenvs were exactly the same). I actually found one solution: I figured the problem was due to the difference in instruction set thanks to these posts: [https://software.intel.com/en-us/forums/intel-distribution-for-python/topic/721634] [Same Python code, same data, different results on different machines They suggested that I use MKL to force which instruction set is used by setting os.environ['MKL_CBWR'] = 'SSE4_2'. I uninstalled numpy and installed intel-numpy (numpy built with mkl) so that I could set os.environ['MKL_CBWR'] = 'SSE4_2'. Now the output of the script is the same for both machines. However, even though the results match, they do not match the result pre mkl (using plain numpy). It would help me a lot to be able to use intel-numpy to reproduce the old results from the server; I have a lot of experiments that took over a week to run, and I would like to be able to use those results without rerunning them. Edits: I've done some more research and I think the problem may be in the Lapack and Blas implementation. I think that MKL and OpenBlas (which is what my default numpy uses) have different implementations which results in different order of operations. So maybe my solution is to continue to use the default numpy, but force the instruction set to be SSE4_2 on my desktop. Is there a way to force the use of "SSE4_2" without using MKL? Do I need to compile numpy from source and compile openblas from source and make sure they have avx disabled? If so, could anyone point me in the right direction to get started? I have found a few sources, but there seems to be a lot of ways to compile from source. [http://numpy-discussion.10968.n7.nabble.com/deterministic-reproducible-matmul-matmult-td43270.html] [How can I compile *without* various instruction sets enabled? If my question is not clear, let me know and I will try to clarify. Additional details: When I run np.__config__.show() using default numpy (not intel-numpy) I get: lapack_opt_info: libraries = ['openblas', 'openblas'] library_dirs = ['/usr/local/lib'] define_macros = [('HAVE_CBLAS', None)] language = c blas_opt_info: libraries = ['openblas', 'openblas'] library_dirs = ['/usr/local/lib'] define_macros = [('HAVE_CBLAS', None)] language = c openblas_info: libraries = ['openblas', 'openblas'] library_dirs = ['/usr/local/lib'] define_macros = [('HAVE_CBLAS', None)] language = c blis_info: NOT AVAILABLE openblas_lapack_info: libraries = ['openblas', 'openblas'] library_dirs = ['/usr/local/lib'] define_macros = [('HAVE_CBLAS', None)] language = c lapack_mkl_info: NOT AVAILABLE blas_mkl_info: NOT AVAILABLE When I run np.__config__.show() with intel-numpy I get: lapack_opt_info: libraries = ['mkl_rt', 'pthread'] library_dirs = ['/opt/anaconda1anaconda2anaconda3/lib'] define_macros = [('SCIPY_MKL_H', None), ('HAVE_CBLAS', None)] include_dirs = ['/opt/anaconda1anaconda2anaconda3/include'] blas_opt_info: libraries = ['mkl_rt', 'pthread'] library_dirs = ['/opt/anaconda1anaconda2anaconda3/lib'] define_macros = [('SCIPY_MKL_H', None), ('HAVE_CBLAS', None)] include_dirs = ['/opt/anaconda1anaconda2anaconda3/include'] lapack_mkl_info: libraries = ['mkl_rt', 'pthread'] library_dirs = ['/opt/anaconda1anaconda2anaconda3/lib'] define_macros = [('SCIPY_MKL_H', None), ('HAVE_CBLAS', None)] include_dirs = ['/opt/anaconda1anaconda2anaconda3/include'] blas_mkl_info: libraries = ['mkl_rt', 'pthread'] library_dirs = ['/opt/anaconda1anaconda2anaconda3/lib'] define_macros = [('SCIPY_MKL_H', None), ('HAVE_CBLAS', None)] include_dirs = ['/opt/anaconda1anaconda2anaconda3/include'] mkl_info: libraries = ['mkl_rt', 'pthread'] library_dirs = ['/opt/anaconda1anaconda2anaconda3/lib'] define_macros = [('SCIPY_MKL_H', None), ('HAVE_CBLAS', None)] include_dirs = ['/opt/anaconda1anaconda2anaconda3/include'] Running lshw on each machine results in: OLD SERVER: description: Computer width: 64 bits capabilities: vsyscall32 *-core description: Motherboard physical id: 0 *-memory description: System memory physical id: 0 size: 47GiB *-cpu:0 product: Intel(R) Xeon(R) CPU X5650 @ 2.67GHz vendor: Intel Corp. physical id: 1 bus info: cpu@0 width: 64 bits capabilities: fpu fpu_exception wp vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp x86-64 constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm pcid dca sse4_1 sse4_2 popcnt aes lahf_lm pti tpr_shadow vnmi flexpriority ept vpid dtherm ida arat *-cpu:1 product: Intel(R) Xeon(R) CPU X5650 @ 2.67GHz vendor: Intel Corp. physical id: 2 bus info: cpu@1 width: 64 bits capabilities: fpu fpu_exception wp vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp x86-64 constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm pcid dca sse4_1 sse4_2 popcnt aes lahf_lm pti tpr_shadow vnmi flexpriority ept vpid dtherm ida arat *-pci:0 description: Host bridge product: 5500 I/O Hub to ESI Port vendor: Intel Corporation physical id: 100 bus info: pci@0000:00:00.0 version: 13 width: 32 bits clock: 33MHz NEW DESKTOP: width: 64 bits capabilities: vsyscall32 *-core description: Motherboard physical id: 0 *-memory description: System memory physical id: 0 size: 31GiB *-cpu product: Intel(R) Core(TM) i5-6600 CPU @ 3.30GHz vendor: Intel Corp. physical id: 1 bus info: cpu@0 size: 1250MHz capacity: 3900MHz width: 64 bits capabilities: fpu fpu_exception wp vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp x86-64 constant_tsc art arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf tsc_known_freq pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault epb invpcid_single pti ssbd ibrs ibpb stibp tpr_shadow vnmi flexpriority ept vpid fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm mpx rdseed adx smap clflushopt intel_pt xsaveopt xsavec xgetbv1 xsaves dtherm ida arat pln pts hwp hwp_notify hwp_act_window hwp_epp flush_l1d cpufreq *-pci description: Host bridge product: Sky Lake Host Bridge/DRAM Registers vendor: Intel Corporation physical id: 100 bus info: pci@0000:00:00.0 version: 07 width: 32 bits clock: 33MHz configuration: driver=skl_uncore resources: irq:0 Continue reading...
