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Subsections


2.4 Libraries

QUANTUM ESPRESSO contains a copy of some needed external libraries:

Optimized vendor-specific libraries often yield huge performance gains with respect to compiled libraries and should be used whenever possible. configure always try to locate the best mathematical libraries.

2.4.0.1 BLAS and LAPACK

QUANTUM ESPRESSO can use any architecture-optimized BLAS and LAPACK replacements, like those contained e.g. in the following libraries:
MKL for Intel CPUs
ACML for AMD CPUs
ESSL for IBM machines

If none of these is available, we suggest that you use the optimized ATLAS library: see
http://math-atlas.sourceforge.net/. Note that ATLAS is not a complete replacement for LAPACK: it contains all of the BLAS, plus the LU code, plus the full storage Cholesky code. Follow the instructions in the ATLAS distributions to produce a full LAPACK replacement.

Sergei Lisenkov reported success and good performances with optimized BLAS by Kazushige Goto. The library is now available under an open-source license: see the GotoBLAS2 page at
http://www.tacc.utexas.edu/tacc-software/gotoblas2/.

2.4.0.2 FFT

QUANTUM ESPRESSO has an internal copy of an old FFTW library. It also supports the newer FFTW3 library and some vendor-specific FFT libraries. configure will first search for vendor-specific FFT libraries; if none is found, it will search for an external FFTW v.3 library; if none is found, it will fall back to the internal copy of FFTW. configure will add the appropriate preprocessing options: to DFLAGS in the make.inc file. If you edit make.inc manually, please note that one and only one among the mentioned preprocessing option must be set.

If you have MKL libraries, you may either use the provided FFTW3 interface (v.10 and later), or directly link FFTW3 from MKL (v.12 and later) or use DFTI (recommended).

2.4.0.3 MPI libraries

MPI libraries are usually needed for parallel execution, unless you are happy with OpenMP-only multicore parallelization. In well-configured machines, configure should find the appropriate parallel compiler for you, and this should find the appropriate libraries. Since often this doesn't happen, especially on PC clusters, see Sec.2.7.6.

Note: since v.6.1, MPI libraries implementing v.3 of the standard (notably, non-blocking broadcast and gather operations) are required.

2.4.0.4 Libraries for accelerators

The accelerated version of the code uses standard CUDA libraries such as cublas, cufft, cusolver and the eigensolver library explicitly developed for QUANTUM ESPRESSO by NVidia and distributed at https://github.com/NVIDIA/Eigensolver_gpu.

2.4.0.5 HDF5

The HDF5 library (https://www.hdfgroup.org/downloads/hdf5/) can be used to perform binary I/O using the HDF5 format.

The user may need to install this library, compiling it with options -enable-fortran, -enable-fortran-2003, and -enable-parallel (see below). These options must be passed to the configure script of the library, not of QUANTUM ESPRESSO.

One can use either the 1.10 or 1.8 version of the library. For the latter the user has to download a version at least as new as 1.8.16.

The path to the root directory of the library (the one containing bin/, include/ and lib/ directories) has to be passed to the configure script of QUANTUM ESPRESSO via the -with-hdf5=... option.

It is possible to use a library with disabled parallelism, but one has to add manually the flag -D__HDF5_SERIAL to the MANUAL_DFLAGS in the make.inc file.

The HDF5 packages provided by many LINUX distributions may also work, but the configure script fails if includes and libraries are not placed under the same root directory. In this case the user should manually set the correct paths in the make.inc file.

2.4.0.6 LIBXC

QUANTUM ESPRESSO can use the libxc library. You need to install libxc first, then: configure --with-libxc --with-libxc-prefix=... --with-libxc-include=.... You may look for "libxc" in make.inc in case of trouble. Note that currently only a (small) subset of functionals implemented in libxc can be used and that the libxc-enabled version cannot use functionals from QUANTUM ESPRESSO. This will change in the future.

2.4.0.7 Other libraries

QUANTUM ESPRESSO can use the MASS vector math library from IBM, if available (only on machines with XLF compiler: likely obsolete).

2.4.0.8 If optimized libraries are not found

The configure script attempts to find optimized libraries, but may fail if they have been installed in non-standard places. You should examine the final value of BLAS_LIBS, LAPACK_LIBS, FFT_LIBS, MPI_LIBS (if needed), MASS_LIBS (IBM only), either in the output of configure or in the generated make.inc, to check whether it found all the libraries that you intend to use.

If some library was not found, you can specify a list of directories to search in the environment variable LIBDIRS, and rerun configure; directories in the list must be separated by spaces. For example:

   ./configure LIBDIRS="/opt/intel/mkl70/lib/32 /usr/lib/math"
If this still fails, you may set some or all of the *_LIBS variables manually and retry. For example:
   ./configure BLAS_LIBS="-L/usr/lib/math -lf77blas -latlas_sse"
Beware that in this case, configure will blindly accept the specified value, and won't do any extra search.


next up previous contents
Next: 2.5 Compilation Up: 2 Installation Previous: 2.3 configure   Contents
Paolo Giannozzi 2019-04-18