OpenBLAS is an optimized BLAS library based on GotoBLAS2 1.13 BSD version.
Please read the documentation on the OpenBLAS wiki pages: https://github.com/xianyi/OpenBLAS/wiki.
We provide official binary packages for the following platform:
- Windows x86/x86_64
You can download them from file hosting on sourceforge.net.
Download from project homepage, https://xianyi.github.com/OpenBLAS/, or check out the code using Git from https://github.com/xianyi/OpenBLAS.git. Buildtime parameters can be chosen in Makefile.rule, see there for a short description of each option. Most can also be given directly on the make or cmake command line.
Building OpenBLAS requires the following to be installed:
- GNU Make
- A C compiler, e.g. GCC or Clang
- A Fortran compiler (optional, for LAPACK)
- IBM MASS (optional, see below)
Simply invoking make
(or gmake
on BSD) will detect the CPU automatically.
To set a specific target CPU, use make TARGET=xxx
, e.g. make TARGET=NEHALEM
.
The full target list is in the file TargetList.txt
.
Set CC
and FC
to point to the cross toolchains, and set HOSTCC
to your host C compiler.
The target must be specified explicitly when cross compiling.
Examples:
-
On an x86 box, compile this library for a loongson3a CPU:
make BINARY=64 CC=mips64el-unknown-linux-gnu-gcc FC=mips64el-unknown-linux-gnu-gfortran HOSTCC=gcc TARGET=LOONGSON3A
-
On an x86 box, compile this library for a loongson3a CPU with loongcc (based on Open64) compiler:
make CC=loongcc FC=loongf95 HOSTCC=gcc TARGET=LOONGSON3A CROSS=1 CROSS_SUFFIX=mips64el-st-linux-gnu- NO_LAPACKE=1 NO_SHARED=1 BINARY=32
A debug version can be built using make DEBUG=1
.
The IBM MASS library consists of a set of mathematical functions for C, C++, and Fortran applications that are tuned for optimum performance on POWER architectures. OpenBLAS with MASS requires a 64-bit, little-endian OS on POWER. The library can be installed as shown:
-
On Ubuntu:
wget -q http://public.dhe.ibm.com/software/server/POWER/Linux/xl-compiler/eval/ppc64le/ubuntu/public.gpg -O- | sudo apt-key add - echo "deb http://public.dhe.ibm.com/software/server/POWER/Linux/xl-compiler/eval/ppc64le/ubuntu/ trusty main" | sudo tee /etc/apt/sources.list.d/ibm-xl-compiler-eval.list sudo apt-get update sudo apt-get install libxlmass-devel.8.1.5
-
On RHEL/CentOS:
wget http://public.dhe.ibm.com/software/server/POWER/Linux/xl-compiler/eval/ppc64le/rhel7/repodata/repomd.xml.key sudo rpm --import repomd.xml.key wget http://public.dhe.ibm.com/software/server/POWER/Linux/xl-compiler/eval/ppc64le/rhel7/ibm-xl-compiler-eval.repo sudo cp ibm-xl-compiler-eval.repo /etc/yum.repos.d/ sudo yum install libxlmass-devel.8.1.5
After installing the MASS library, compile OpenBLAS with USE_MASS=1
.
For example, to compile on Power8 with MASS support: make USE_MASS=1 TARGET=POWER8
.
Use PREFIX=
when invoking make
, for example
make install PREFIX=your_installation_directory
The default installation directory is /opt/OpenBLAS
.
Please read GotoBLAS_01Readme.txt
for older CPU models already supported by the 2010 GotoBLAS.
- Intel Xeon 56xx (Westmere): Used GotoBLAS2 Nehalem codes.
- Intel Sandy Bridge: Optimized Level-3 and Level-2 BLAS with AVX on x86-64.
- Intel Haswell: Optimized Level-3 and Level-2 BLAS with AVX2 and FMA on x86-64.
- Intel Skylake-X: Optimized Level-3 and Level-2 BLAS with AVX512 and FMA on x86-64.
- AMD Bobcat: Used GotoBLAS2 Barcelona codes.
- AMD Bulldozer: x86-64 ?GEMM FMA4 kernels. (Thanks to Werner Saar)
- AMD PILEDRIVER: Uses Bulldozer codes with some optimizations.
- AMD STEAMROLLER: Uses Bulldozer codes with some optimizations.
- AMD ZEN: Uses Haswell codes with some optimizations.
- ICT Loongson 3A: Optimized Level-3 BLAS and the part of Level-1,2.
- ICT Loongson 3B: Experimental
- ARMv6: Optimized BLAS for vfpv2 and vfpv3-d16 (e.g. BCM2835, Cortex M0+)
- ARMv7: Optimized BLAS for vfpv3-d32 (e.g. Cortex A8, A9 and A15)
- ARMv8: Basic ARMV8 with small caches, optimized Level-3 and Level-2 BLAS
- Cortex-A53: same as ARMV8 (different cpu specifications)
- Cortex A57: Optimized Level-3 and Level-2 functions
- Cortex A72: same as A57 ( different cpu specifications)
- Cortex A73: same as A57 (different cpu specifications)
- Falkor: same as A57 (different cpu specifications)
- ThunderX: Optimized some Level-1 functions
- ThunderX2T99: Optimized Level-3 BLAS and parts of Levels 1 and 2
- TSV110: Optimized some Level-3 helper functions
- POWER8: Optimized BLAS, only for PPC64LE (Little Endian), only with
USE_OPENMP=1
- POWER9: Optimized Level-3 BLAS (real) and some Level-1,2. PPC64LE with OpenMP only.
- Z13: Optimized Level-3 BLAS and Level-1,2
- Z14: Optimized Level-3 BLAS and (single precision) Level-1,2
OpenBLAS can be built for multiple targets with runtime detection of the target cpu by specifiying DYNAMIC_ARCH=1 in Makefile.rule, on the gmake command line or as -DDYNAMIC_ARCH=TRUE in cmake. For x86_64, the list of targets this activates contains Prescott, Core2, Nehalem, Barcelona, Sandybridge, Bulldozer, Piledriver, Steamroller, Excavator, Haswell, Zen, SkylakeX. For cpu generations not included in this list, the corresponding older model is used. If you also specify DYNAMIC_OLDER=1, specific support for Penryn, Dunnington, Opteron, Opteron/SSE3, Bobcat, Atom and Nano is added. Finally there is an option DYNAMIC_LIST that allows to specify an individual list of targets to include instead of the default. DYNAMIC_ARCH is also supported on x86, where it translates to Katmai, Coppermine, Northwood, Prescott, Banias, Core2, Penryn, Dunnington, Nehalem, Athlon, Opteron, Opteron_SSE3, Barcelona, Bobcat, Atom and Nano. On ARMV8, it enables support for CortexA53, CortexA57, CortexA72, CortexA73, Falkor, ThunderX, ThunderX2T99, TSV110 as well as generic ARMV8 cpus. For POWER, the list encompasses POWER6, POWER8 and POWER9, on ZARCH it comprises Z13 and Z14. The TARGET option can be used in conjunction with DYNAMIC_ARCH=1 to specify which cpu model should be assumed for all the common code in the library, usually you will want to set this to the oldest model you expect to encounter. Please note that it is not possible to combine support for different architectures, so no combined 32 and 64 bit or x86_64 and arm64 in the same library.
- GNU/Linux
- MinGW or Visual Studio (CMake)/Windows: Please read https://github.com/xianyi/OpenBLAS/wiki/How-to-use-OpenBLAS-in-Microsoft-Visual-Studio.
- Darwin/macOS/OSX/iOS: Experimental. Although GotoBLAS2 already supports Darwin, we are not OSX/iOS experts.
- FreeBSD: Supported by the community. We don't actively test the library on this OS.
- OpenBSD: Supported by the community. We don't actively test the library on this OS.
- NetBSD: Supported by the community. We don't actively test the library on this OS.
- DragonFly BSD: Supported by the community. We don't actively test the library on this OS.
- Android: Supported by the community. Please read https://github.com/xianyi/OpenBLAS/wiki/How-to-build-OpenBLAS-for-Android.
- AIX: Supported on PPC up to POWER8
- Haiku: Supported by the community. We don't actively test the library on this OS.
- SunOS: Supported by the community. We don't actively test the library on this OS:
Statically link with libopenblas.a
or dynamically link with -lopenblas
if OpenBLAS was
compiled as a shared library.
Environment variables are used to specify a maximum number of threads. For example,
export OPENBLAS_NUM_THREADS=4
export GOTO_NUM_THREADS=4
export OMP_NUM_THREADS=4
The priorities are OPENBLAS_NUM_THREADS
> GOTO_NUM_THREADS
> OMP_NUM_THREADS
.
If you compile this library with USE_OPENMP=1
, you should set the OMP_NUM_THREADS
environment variable; OpenBLAS ignores OPENBLAS_NUM_THREADS
and GOTO_NUM_THREADS
when
compiled with USE_OPENMP=1
.
We provide the following functions to control the number of threads at runtime:
void goto_set_num_threads(int num_threads);
void openblas_set_num_threads(int num_threads);
If you compile this library with USE_OPENMP=1
, you should use the above functions too.
Please submit an issue in https://github.com/xianyi/OpenBLAS/issues.
- OpenBLAS users mailing list: https://groups.google.com/forum/#!forum/openblas-users
- OpenBLAS developers mailing list: https://groups.google.com/forum/#!forum/openblas-dev
Please see Changelog.txt to view the differences between OpenBLAS and GotoBLAS2 1.13 BSD version.
- Please read the FAQ first.
- Please use GCC version 4.6 and above to compile Sandy Bridge AVX kernels on Linux/MinGW/BSD.
- Please use Clang version 3.1 and above to compile the library on Sandy Bridge microarchitecture. Clang 3.0 will generate the wrong AVX binary code.
- Please use GCC version 6 or LLVM version 6 and above to compile Skylake AVX512 kernels.
- The number of CPUs/cores should be less than or equal to 256. On Linux
x86_64
(amd64
), there is experimental support for up to 1024 CPUs/cores and 128 numa nodes if you build the library withBIGNUMA=1
. - OpenBLAS does not set processor affinity by default.
On Linux, you can enable processor affinity by commenting out the line
NO_AFFINITY=1
in Makefile.rule. However, note that this may cause a conflict with R parallel. - On Loongson 3A,
make test
may fail with apthread_create
error (EAGAIN
). However, it will be okay when you run the same test case on the shell.
- Check for open issues or open a fresh issue to start a discussion around a feature idea or a bug.
- Fork the OpenBLAS repository to start making your changes.
- Write a test which shows that the bug was fixed or that the feature works as expected.
- Send a pull request. Make sure to add yourself to
CONTRIBUTORS.md
.
Please read this wiki page.