Include Files

Description

The

dss_create

routine initializes the solver. After the call to

dss_create

, all subsequent invocations of the

Intel® oneAPI Math Kernel Library

DSS routines must use the value of the handle returned by

dss_create

.

The default value of the parameter

opt

is

MKL_DSS_MSG_LVL_WARNING

+

MKL_DSS_TERM_LVL_ERROR

.

By default, the DSS routines use double precision for solving systems of linear equations. The precision used by the DSS routines can be set to single mode by adding the following value to the

opt

parameter:

MKL_DSS_SINGLE_PRECISION

.

Input data and internal arrays are required to have single precision.

By default, the DSS routines use Fortran style (one-based) indexing for input arrays of integer types (the first value is referenced as array element 1). To set indexing to C style (the first value is referenced as array element 0), add the following value to the

opt

parameter:

MKL_DSS_ZERO_BASED_INDEXING

.

The

opt

parameter can also control number of refinement steps used on the solution stage by specifying the two following values:

MKL_DSS_REFINEMENT_OFF

- maximum number of refinement steps is set to zero;

MKL_DSS_REFINEMENT_ON

(default value) - maximum number of refinement steps is set to 2.

By default, DSS uses in-core computations. To launch the out-of-core version of DSS (OOC DSS) you can add to this parameter one of two possible values:

MKL_DSS_OOC_STRONG

and

MKL_DSS_OOC_VARIABLE

.

MKL_DSS_OOC_STRONG

- OOC DSS is used.

MKL_DSS_OOC_VARIABLE

- if the memory needed for the matrix factors is less than the value of the environment variable

MKL_PARDISO_OOC_MAX_CORE_SIZE

, then the OOC DSS uses the in-core kernels of

Intel® oneAPI Math Kernel Library

PARDISO, otherwise it uses the OOC computations.

The variable

MKL_PARDISO_OOC_MAX_CORE_SIZE

defines the maximum size of RAM allowed for storing work arrays associated with the matrix factors. It is ignored if

MKL_DSS_OOC_STRONG

is set. The default value of

MKL_PARDISO_OOC_MAX_CORE_SIZE

is 2000 MB. This value and default path and file name for storing temporary data can be changed using the configuration file

pardiso_ooc.cfg

or command line (See more details in the description of the pardiso routine).