libMesh
|
The Partitioner
class provides a uniform interface for partitioning algorithms.
More...
#include <partitioner.h>
Public Member Functions | |
Partitioner () | |
Constructor. More... | |
Partitioner (const Partitioner &)=default | |
Copy/move ctor, copy/move assignment operator, and destructor are all explicitly defaulted for this class. More... | |
Partitioner (Partitioner &&)=default | |
Partitioner & | operator= (const Partitioner &)=default |
Partitioner & | operator= (Partitioner &&)=default |
virtual | ~Partitioner ()=default |
virtual PartitionerType | type () const |
virtual std::unique_ptr< Partitioner > | clone () const =0 |
virtual void | partition (MeshBase &mesh, const unsigned int n) |
Partitions the MeshBase into n parts by setting processor_id() on Nodes and Elems. More... | |
virtual void | partition (MeshBase &mesh) |
Partitions the MeshBase into mesh.n_processors() by setting processor_id() on Nodes and Elems. More... | |
virtual void | partition_range (MeshBase &, MeshBase::element_iterator, MeshBase::element_iterator, const unsigned int) |
Partitions elements in the range (it, end) into n parts. More... | |
void | repartition (MeshBase &mesh, const unsigned int n) |
Repartitions the MeshBase into n parts. More... | |
void | repartition (MeshBase &mesh) |
Repartitions the MeshBase into mesh.n_processors() parts. More... | |
virtual void | attach_weights (ErrorVector *) |
Attach weights that can be used for partitioning. More... | |
Static Public Member Functions | |
static std::unique_ptr< Partitioner > | build (const PartitionerType solver_package) |
Builds a Partitioner of the type specified by partitioner_type . More... | |
static void | partition_unpartitioned_elements (MeshBase &mesh) |
These functions assign processor IDs to newly-created elements (in parallel) which are currently assigned to processor 0. More... | |
static void | partition_unpartitioned_elements (MeshBase &mesh, const unsigned int n) |
static void | set_parent_processor_ids (MeshBase &mesh) |
This function is called after partitioning to set the processor IDs for the inactive parent elements. More... | |
static void | set_node_processor_ids (MeshBase &mesh) |
This function is called after partitioning to set the processor IDs for the nodes. More... | |
static void | processor_pairs_to_interface_nodes (MeshBase &mesh, std::map< std::pair< processor_id_type, processor_id_type >, std::set< dof_id_type >> &processor_pair_to_nodes) |
On the partitioning interface, a surface is shared by two and only two processors. More... | |
static void | set_interface_node_processor_ids_linear (MeshBase &mesh) |
Nodes on the partitioning interface is linearly assigned to each pair of processors. More... | |
static void | set_interface_node_processor_ids_BFS (MeshBase &mesh) |
Nodes on the partitioning interface is clustered into two groups BFS (Breadth First Search)scheme for per pair of processors. More... | |
static void | set_interface_node_processor_ids_petscpartitioner (MeshBase &mesh) |
Nodes on the partitioning interface is partitioned into two groups using a PETSc partitioner for each pair of processors. More... | |
Protected Member Functions | |
bool | single_partition (MeshBase &mesh) |
Trivially "partitions" the mesh for one processor. More... | |
bool | single_partition_range (MeshBase::element_iterator it, MeshBase::element_iterator end) |
Slightly generalized version of single_partition which acts on a range of elements defined by the pair of iterators (it, end). More... | |
virtual void | _do_partition (MeshBase &mesh, const unsigned int n)=0 |
This is the actual partitioning method which must be overridden in derived classes. More... | |
virtual void | _do_repartition (MeshBase &mesh, const unsigned int n) |
This is the actual re-partitioning method which can be overridden in derived classes. More... | |
virtual void | _find_global_index_by_pid_map (const MeshBase &mesh) |
Construct contiguous global indices for the current partitioning. More... | |
virtual void | build_graph (const MeshBase &mesh) |
Build a dual graph for partitioner. More... | |
void | assign_partitioning (MeshBase &mesh, const std::vector< dof_id_type > &parts) |
Assign the computed partitioning to the mesh. More... | |
Protected Attributes | |
ErrorVector * | _weights |
The weights that might be used for partitioning. More... | |
std::unordered_map< dof_id_type, dof_id_type > | _global_index_by_pid_map |
Maps active element ids into a contiguous range, as needed by parallel partitioner. More... | |
std::vector< dof_id_type > | _n_active_elem_on_proc |
The number of active elements on each processor. More... | |
std::vector< std::vector< dof_id_type > > | _dual_graph |
A dual graph corresponds to the mesh, and it is typically used in paritioner. More... | |
std::vector< Elem * > | _local_id_to_elem |
Static Protected Attributes | |
static const dof_id_type | communication_blocksize |
The blocksize to use when doing blocked parallel communication. More... | |
The Partitioner
class provides a uniform interface for partitioning algorithms.
It takes a reference to a MeshBase
object as input, which it will partition into a number of subdomains.
Definition at line 51 of file partitioner.h.
|
inline |
Constructor.
Definition at line 58 of file partitioner.h.
|
default |
Copy/move ctor, copy/move assignment operator, and destructor are all explicitly defaulted for this class.
|
default |
|
virtualdefault |
|
protectedpure virtual |
This is the actual partitioning method which must be overridden in derived classes.
It is called via the public partition() method above by the user.
Implemented in OverlappingTestPartitioner, libMesh::SubdomainPartitioner, libMesh::CentroidPartitioner, libMesh::ParmetisPartitioner, libMesh::MappedSubdomainPartitioner, libMesh::SFCPartitioner, libMesh::MortonSFCPartitioner, libMesh::MetisPartitioner, libMesh::HilbertSFCPartitioner, libMesh::LinearPartitioner, and ContrivedPartitioner.
Referenced by _do_repartition(), and partition().
|
inlineprotectedvirtual |
This is the actual re-partitioning method which can be overridden in derived classes.
Reimplemented in libMesh::ParmetisPartitioner.
Definition at line 251 of file partitioner.h.
References _do_partition().
Referenced by repartition().
|
protectedvirtual |
Construct contiguous global indices for the current partitioning.
The global indices are ordered part-by-part
Definition at line 1067 of file partitioner.C.
References _global_index_by_pid_map, _n_active_elem_on_proc, TIMPI::Communicator::allgather(), libMesh::ParallelObject::comm(), libMesh::MeshTools::create_bounding_box(), libMesh::MeshCommunication::find_local_indices(), libMesh::make_range(), mesh, libMesh::MeshBase::n_active_local_elem(), libMesh::ParallelObject::n_processors(), and libMesh::Parallel::sync_dofobject_data_by_id().
Referenced by build_graph().
|
protected |
Assign the computed partitioning to the mesh.
Definition at line 1334 of file partitioner.C.
References _global_index_by_pid_map, _n_active_elem_on_proc, libMesh::ParallelObject::comm(), libMesh::libmesh_assert(), libMesh::make_range(), mesh, libMesh::MeshBase::n_active_local_elem(), libMesh::MeshBase::n_partitions(), libMesh::ParallelObject::n_processors(), and libMesh::ParallelObject::processor_id().
|
inlinevirtual |
Attach weights that can be used for partitioning.
This ErrorVector should be exactly the same on every processor and should have mesh->max_elem_id() entries.
Reimplemented in libMesh::MetisPartitioner.
Definition at line 213 of file partitioner.h.
|
static |
Builds a Partitioner
of the type specified by partitioner_type
.
Definition at line 158 of file partitioner.C.
References libMesh::CENTROID_PARTITIONER, libMesh::Utility::enum_to_string(), libMesh::HILBERT_SFC_PARTITIONER, libMesh::LINEAR_PARTITIONER, libMesh::MAPPED_SUBDOMAIN_PARTITIONER, libMesh::METIS_PARTITIONER, libMesh::MORTON_SFC_PARTITIONER, libMesh::PARMETIS_PARTITIONER, libMesh::SFC_PARTITIONER, and libMesh::SUBDOMAIN_PARTITIONER.
Referenced by libMesh::DistributedMesh::DistributedMesh(), libMesh::ReplicatedMesh::ReplicatedMesh(), PartitionerTest< PartitionerSubclass, MeshClass >::testBuild(), and MeshDeletionsTest::testDeleteElem().
|
protectedvirtual |
Build a dual graph for partitioner.
Reimplemented in libMesh::ParmetisPartitioner.
Definition at line 1111 of file partitioner.C.
References _dual_graph, _find_global_index_by_pid_map(), _global_index_by_pid_map, _local_id_to_elem, _n_active_elem_on_proc, libMesh::as_range(), libMesh::MeshBase::get_constraint_rows(), libMesh::DofObject::id(), libMesh::libmesh_assert(), libMesh::libmesh_ignore(), libMesh::make_range(), mesh, libMesh::MeshBase::n_active_local_elem(), and libMesh::ParallelObject::processor_id().
|
pure virtual |
This is used when copying meshes, and must be overridden in the derived classes.
Implemented in OverlappingTestPartitioner, libMesh::CentroidPartitioner, libMesh::SubdomainPartitioner, libMesh::ParmetisPartitioner, libMesh::MortonSFCPartitioner, libMesh::HilbertSFCPartitioner, libMesh::SFCPartitioner, libMesh::MappedSubdomainPartitioner, libMesh::LinearPartitioner, libMesh::MetisPartitioner, and ContrivedPartitioner.
|
default |
|
default |
Partitions the MeshBase
into n
parts by setting processor_id() on Nodes and Elems.
Definition at line 195 of file partitioner.C.
References _do_partition(), libMesh::ParallelObject::comm(), libMesh::MeshTools::libmesh_assert_valid_remote_elems(), mesh, libMesh::MeshBase::n_active_elem(), partition_unpartitioned_elements(), libMesh::MeshBase::redistribute(), libMesh::MeshBase::set_n_partitions(), set_node_processor_ids(), set_parent_processor_ids(), single_partition(), and libMesh::MeshBase::update_post_partitioning().
Referenced by libMesh::ParmetisPartitioner::_do_repartition(), and partition().
|
virtual |
Partitions the MeshBase
into mesh.n_processors()
by setting processor_id() on Nodes and Elems.
Definition at line 188 of file partitioner.C.
References mesh, libMesh::ParallelObject::n_processors(), and partition().
|
inlinevirtual |
Partitions elements in the range (it, end) into n parts.
The mesh from which the iterators are created must also be passed in, since it is a parallel object and has other useful information in it.
Although partition_range() is part of the public Partitioner interface, it should not generally be called by applications. Its main purpose is to support the SubdomainPartitioner, which uses it internally to individually partition ranges of elements before combining them into the final partitioning. Most of the time, the protected _do_partition() function is implemented in terms of partition_range() by passing a range which includes all the elements of the Mesh.
Reimplemented in libMesh::CentroidPartitioner, libMesh::MappedSubdomainPartitioner, libMesh::SFCPartitioner, libMesh::LinearPartitioner, and libMesh::MetisPartitioner.
Definition at line 137 of file partitioner.h.
Referenced by libMesh::SubdomainPartitioner::_do_partition().
|
static |
These functions assign processor IDs to newly-created elements (in parallel) which are currently assigned to processor 0.
Definition at line 344 of file partitioner.C.
References mesh, and libMesh::ParallelObject::n_processors().
Referenced by partition(), and repartition().
|
static |
Definition at line 351 of file partitioner.C.
References libMesh::as_range(), libMesh::ParallelObject::comm(), libMesh::MeshTools::create_bounding_box(), distance(), libMesh::MeshCommunication::find_global_indices(), libMesh::make_range(), mesh, libMesh::MeshTools::n_elem(), and libMesh::ParallelObject::n_processors().
|
static |
On the partitioning interface, a surface is shared by two and only two processors.
Try to find which pair of processors corresponds to which surfaces, and store their nodes.
Definition at line 578 of file partitioner.C.
References libMesh::ParallelObject::comm(), libMesh::DofObject::invalid_processor_id, libMesh::libmesh_assert(), mesh, and n_nodes.
Referenced by set_interface_node_processor_ids_BFS(), set_interface_node_processor_ids_linear(), and set_interface_node_processor_ids_petscpartitioner().
Repartitions the MeshBase
into n
parts.
(Some partitioning algorithms can repartition more efficiently than computing a new partitioning from scratch.) The default behavior is to simply call this->partition(mesh,n).
Definition at line 262 of file partitioner.C.
References _do_repartition(), mesh, libMesh::MeshBase::n_active_elem(), partition_unpartitioned_elements(), libMesh::MeshBase::set_n_partitions(), set_node_processor_ids(), set_parent_processor_ids(), and single_partition().
Referenced by repartition().
void libMesh::Partitioner::repartition | ( | MeshBase & | mesh | ) |
Repartitions the MeshBase
into mesh.n_processors()
parts.
This is required since some partitioning algorithms can repartition more efficiently than computing a new partitioning from scratch.
Definition at line 255 of file partitioner.C.
References mesh, libMesh::ParallelObject::n_processors(), and repartition().
|
static |
Nodes on the partitioning interface is clustered into two groups BFS (Breadth First Search)scheme for per pair of processors.
Definition at line 656 of file partitioner.C.
References libMesh::MeshTools::build_nodes_to_elem_map(), libMesh::ParallelObject::comm(), libMesh::MeshTools::find_nodal_neighbors(), mesh, libMesh::MeshBase::node_ref(), libMesh::DofObject::processor_id(), and processor_pairs_to_interface_nodes().
Referenced by set_node_processor_ids().
|
static |
Nodes on the partitioning interface is linearly assigned to each pair of processors.
Definition at line 631 of file partitioner.C.
References libMesh::ParallelObject::comm(), mesh, libMesh::MeshBase::node_ref(), libMesh::DofObject::processor_id(), and processor_pairs_to_interface_nodes().
Referenced by set_node_processor_ids().
|
static |
Nodes on the partitioning interface is partitioned into two groups using a PETSc partitioner for each pair of processors.
Definition at line 737 of file partitioner.C.
References libMesh::MeshTools::build_nodes_to_elem_map(), libMesh::ParallelObject::comm(), libMesh::MeshTools::find_nodal_neighbors(), libMesh::is, libMesh::libmesh_ignore(), mesh, libMesh::MeshBase::node_ref(), libMesh::DofObject::processor_id(), and processor_pairs_to_interface_nodes().
Referenced by set_node_processor_ids().
|
static |
This function is called after partitioning to set the processor IDs for the nodes.
By definition, a Node's processor ID is the minimum processor ID for all of the elements which share the node.
Definition at line 851 of file partitioner.C.
References libMesh::as_range(), libMesh::Node::choose_processor_id(), libMesh::ParallelObject::comm(), libMesh::DofObject::id(), libMesh::DofObject::invalid_processor_id, libMesh::MeshBase::is_serial(), libMesh::libmesh_assert(), mesh, libMesh::MeshTools::n_elem(), libMesh::MeshTools::n_levels(), libMesh::MeshBase::node_ref(), libMesh::on_command_line(), libMesh::DofObject::processor_id(), set_interface_node_processor_ids_BFS(), set_interface_node_processor_ids_linear(), set_interface_node_processor_ids_petscpartitioner(), and libMesh::Parallel::sync_node_data_by_element_id().
Referenced by libMesh::MeshRefinement::_refine_elements(), libMesh::UnstructuredMesh::all_first_order(), partition(), libMesh::XdrIO::read(), repartition(), and libMesh::BoundaryInfo::sync().
|
static |
This function is called after partitioning to set the processor IDs for the inactive parent elements.
A parent's processor ID is the same as its first child.
Definition at line 425 of file partitioner.C.
References libMesh::as_range(), libMesh::Elem::child_ref_range(), libMesh::ParallelObject::comm(), communication_blocksize, libMesh::DofObject::invalid_processor_id, libMesh::DofObject::invalidate_processor_id(), libMesh::MeshBase::is_serial(), libMesh::libmesh_assert(), libMesh::libmesh_ignore(), libMesh::MeshBase::max_elem_id(), mesh, TIMPI::Communicator::min(), libMesh::MeshTools::n_elem(), libMesh::Elem::parent(), libMesh::DofObject::processor_id(), and libMesh::Elem::total_family_tree().
Referenced by partition(), and repartition().
|
protected |
Trivially "partitions" the mesh for one processor.
Simply loops through the elements and assigns all of them to processor 0. Is is provided as a separate function so that derived classes may use it without reimplementing it.
Returns true
iff any processor id was changed.
Definition at line 297 of file partitioner.C.
References libMesh::ParallelObject::comm(), TIMPI::Communicator::max(), mesh, libMesh::MeshBase::redistribute(), and single_partition_range().
Referenced by libMesh::SubdomainPartitioner::_do_partition(), partition(), and repartition().
|
protected |
Slightly generalized version of single_partition which acts on a range of elements defined by the pair of iterators (it, end).
Returns true
iff any processor id was changed.
Definition at line 319 of file partitioner.C.
References libMesh::as_range(), and libMesh::DofObject::processor_id().
Referenced by libMesh::LinearPartitioner::partition_range(), libMesh::MetisPartitioner::partition_range(), libMesh::MappedSubdomainPartitioner::partition_range(), libMesh::SFCPartitioner::partition_range(), libMesh::CentroidPartitioner::partition_range(), and single_partition().
|
virtual |
Reimplemented in libMesh::CentroidPartitioner, libMesh::SubdomainPartitioner, libMesh::ParmetisPartitioner, libMesh::MortonSFCPartitioner, libMesh::SFCPartitioner, libMesh::HilbertSFCPartitioner, libMesh::MappedSubdomainPartitioner, libMesh::LinearPartitioner, and libMesh::MetisPartitioner.
Definition at line 151 of file partitioner.C.
References libMesh::INVALID_PARTITIONER.
|
protected |
A dual graph corresponds to the mesh, and it is typically used in paritioner.
A vertex represents an element, and its neighbors are the element neighbors.
Definition at line 302 of file partitioner.h.
Referenced by build_graph().
|
protected |
Maps active element ids into a contiguous range, as needed by parallel partitioner.
Definition at line 286 of file partitioner.h.
Referenced by _find_global_index_by_pid_map(), assign_partitioning(), and build_graph().
|
protected |
Definition at line 305 of file partitioner.h.
Referenced by build_graph().
|
protected |
The number of active elements on each processor.
Definition at line 295 of file partitioner.h.
Referenced by _find_global_index_by_pid_map(), assign_partitioning(), and build_graph().
|
protected |
The weights that might be used for partitioning.
Definition at line 281 of file partitioner.h.
Referenced by libMesh::MetisPartitioner::attach_weights(), and libMesh::MetisPartitioner::partition_range().
|
staticprotected |
The blocksize to use when doing blocked parallel communication.
This limits the maximum vector size which can be used in a single communication step.
Definition at line 258 of file partitioner.h.
Referenced by set_parent_processor_ids().