Section DBCSR

• Configuration options for the DBCSR library.

• Section path: CP2K_INPUT / GLOBAL / DBCSR

• This section cannot be repeated.

• This section cites the following references: [Borstnik2014] [Schuett2016]

• Subsections

  • ACC

• Keywords

  • AVG_ELEMENTS_IMAGES
  • COMM_THREAD_LOAD
  • MAX_ELEMENTS_PER_BLOCK
  • MM_DRIVER
  • MM_STACK_SIZE
  • MULTREC_LIMIT
  • NUM_LAYERS_3D
  • NUM_MULT_IMAGES
  • N_SIZE_MNK_STACKS
  • USE_COMM_THREAD
  • USE_MPI_ALLOCATOR
  • USE_MPI_RMA

• Keyword descriptions

  AVG_ELEMENTS_IMAGES
  	AVG_ELEMENTS_IMAGES {Integer}
  	Average number of elements (dense limit) for each image, which also corresponds to the average number of elements exchanged between MPI processes during the operations. A negative or zero value means unlimited.
  	This keyword cannot be repeated and it expects precisely one integer.
  	Default value: -1

  COMM_THREAD_LOAD
  	COMM_THREAD_LOAD {Integer}
  	If a communications thread is used, specify how much multiplication workload (%) the thread should perform in addition to communication tasks. A negative value leaves the decision up to DBCSR.
  	This keyword cannot be repeated and it expects precisely one integer.
  	Default value: -1

  MAX_ELEMENTS_PER_BLOCK
  	MAX_ELEMENTS_PER_BLOCK {Integer}
  	Default block size for turning dense matrices in blocked ones
  	This keyword cannot be repeated and it expects precisely one integer.
  	Default value: 32

  MM_DRIVER
  	MM_DRIVER {Keyword}
  	Select which backend to use preferably for matrix block multiplications on the host.
  	This keyword cannot be repeated and it expects precisely one keyword.
  	Default value: AUTO
  	List of valid keywords: AUTO Choose automatically the best available driver BLAS BLAS (requires the BLAS library at link time) MATMUL Fortran MATMUL SMM Library optimised for Small Matrix Multiplies (requires the SMM library at link time) XSMM Intel's libxsmm

  MM_STACK_SIZE
  	MM_STACK_SIZE {Integer}
  	Size of multiplication parameter stack. A negative value leaves the decision up to DBCSR.
  	This keyword cannot be repeated and it expects precisely one integer.
  	Default value: -1

  MULTREC_LIMIT
  	MULTREC_LIMIT {Integer}
  	Recursion limit of cache oblivious multrec algorithm.
  	This keyword cannot be repeated and it expects precisely one integer.
  	Default value: 512

  NUM_LAYERS_3D
  	NUM_LAYERS_3D {Integer}
  	Number of layers for the 3D multplication algorithm.
  	This keyword cannot be repeated and it expects precisely one integer.
  	Default value: 1

  NUM_MULT_IMAGES
  	NUM_MULT_IMAGES {Integer}
  	Multiplicative factor for number of virtual images.
  	This keyword cannot be repeated and it expects precisely one integer.
  	Default value: 1

  N_SIZE_MNK_STACKS
  	N_SIZE_MNK_STACKS {Integer}
  	Number of stacks to use for distinct atomic sizes (e.g., 2 for a system of mostly waters).
  	This keyword cannot be repeated and it expects precisely one integer.
  	Default value: 3

  USE_COMM_THREAD
  	USE_COMM_THREAD {Logical}
  	During multiplication, use a thread to periodically poll MPI to progress outstanding message completions. This is beneficial on systems without a DMA-capable network adapter e.g. Cray XE6.
  	This keyword cannot be repeated and it expects precisely one logical.
  	Default value: .TRUE.

  USE_MPI_ALLOCATOR
  	USE_MPI_ALLOCATOR {Logical}
  	Use MPI allocator to allocate buffers used in MPI communications.
  	This keyword cannot be repeated and it expects precisely one logical.
  	Default value: .TRUE.

  USE_MPI_RMA
  	USE_MPI_RMA {Logical}
  	Use RMA for MPI communications for each image, which also corresponds to the number of elements exchanged between MPI processes during the operations.
  	This keyword cannot be repeated and it expects precisely one logical.
  	Default value: .FALSE.