BlockWeightedPartitioner

Partition mesh by weighting blocks

Overview

Under multiphysics environment, some mesh blocks have more variables and more work load than others . In parallel, the work is spread out based on partitioners that assign equal number of elements to each processor. This will causes imbalanced simulations. BlockWeightedPartitioner allow users to specify different weights for different blocks, e.g., low weights for light blocks and high weights for heavy blocks. Weights should be proportional to the relative numbers of DOFs per element in each mesh block. The weights do not need to be pre-normalized to any particular number. Small numbers are better large numbers, e.g., 1 vs 2 is better than 1000 vs 2000. Usage:

[Mesh]
  type = FileMesh
  file = block_weighted_partitioner.e

  [Partitioner]
    type = BlockWeightedPartitioner
    block = '1 2 3'
    weight = '3 1 10'
  []
[]

An example:

Weighted partition into 4 subdomains

Regular partition into 4 subdomains

Input Parameters

blockThe list of block ids (SubdomainID) that this object will be applied
C++ Type:std::vector<SubdomainName>
Controllable:No
Description:The list of block ids (SubdomainID) that this object will be applied
weightThe list of weights (integer) that specify how heavy each block is
C++ Type:std::vector<unsigned long>
Controllable:No
Description:The list of weights (integer) that specify how heavy each block is

Required Parameters

apply_element_weightTrueIndicate if we are going to apply element weights to partitioners
Default:True
C++ Type:bool
Controllable:No
Description:Indicate if we are going to apply element weights to partitioners
apply_side_weightFalseIndicate if we are going to apply side weights to partitioners
Default:False
C++ Type:bool
Controllable:No
Description:Indicate if we are going to apply side weights to partitioners
num_cores_per_compute_node1Number of cores per compute node for hierarchical partitioning
Default:1
C++ Type:unsigned int
Controllable:No
Description:Number of cores per compute node for hierarchical partitioning
part_packageparmetisThe external package is used for partitioning the mesh via PETSc
Default:parmetis
C++ Type:MooseEnum
Options:parmetis, ptscotch, chaco, party, hierarch
Controllable:No
Description:The external package is used for partitioning the mesh via PETSc

Optional Parameters

control_tagsAdds user-defined labels for accessing object parameters via control logic.
C++ Type:std::vector<std::string>
Controllable:No
Description:Adds user-defined labels for accessing object parameters via control logic.
enableTrueSet the enabled status of the MooseObject.
Default:True
C++ Type:bool
Controllable:No
Description:Set the enabled status of the MooseObject.

Advanced Parameters

(../moose/test/tests/partitioners/block_weighted_partitioner/block_weighted_partitioner.i)

[Mesh]
  type = FileMesh
  file = block_weighted_partitioner.e

  [Partitioner]
    type = BlockWeightedPartitioner
    block = '1 2 3'
    weight = '3 1 10'
  []
[]

[Variables]
  [u]
  []
[]

[Kernels]
  [diff]
    type = Diffusion
    variable = u
  []
[]

[BCs]
  [left]
    type = DirichletBC
    variable = u
    boundary = 'left'
    value = 0
  []
  [right]
    type = DirichletBC
    variable = u
    boundary = 'right'
    value = 1
  []
[]

[Executioner]
  type = Steady
  solve_type = Newton
  petsc_options_iname = '-pc_type -pc_hypre_type'
  petsc_options_value = 'hypre boomeramg'
[]

[Outputs]
  exodus = true
[]

[AuxVariables]
  [pid]
    family = MONOMIAL
    order = CONSTANT
  []
  [npid]
    family = Lagrange
    order = first
  []
[]

[AuxKernels]
  [pid_aux]
    type = ProcessorIDAux
    variable = pid
    execute_on = 'INITIAL'
  []
  [npid_aux]
    type = ProcessorIDAux
    variable = npid
    execute_on = 'INITIAL'
  []
[]