A SIBLING-MERGE or REPARTITION stage (docs/amr_mg_depth.md §5.6, WO4b; docs/amr_mg_core_boundary.md §5): the moved level lands on a decomposition of its own grid on FEWER ranks — agglomerated(d) for a sibling merge, a fresh proportional ORB on the first np_L ranks for a repartition, both chosen by core's chooseStageTarget — and the ladder continues there as a DistributedFlowMultigrid on the stage's sub-communicator, with its own lockstep lifts, its own halos and, where it blocks again, its own stage. More...

#include <distributed_flow_mg.hpp>

Inheritance diagram for peclet::amr::DistributedStage< Dim, Bits >:

Public Types
using	Base = MgStage< Dim, Bits >
	the stage interface

using	Octree = typename Base::Octree
	a level's cells on one block

using	Decomposition = typename Base::Decomposition
	the target partition's type

using	DO = DistributedOctree< Dim, Bits >
	the level the stage fires at

using	Poisson = AmrPoisson< Dim, Bits >
	that level's FV operator

using	MG = DistributedFlowMultigrid< Dim, Bits >
	the continued ladder

using	Policy = typename MG::StagePolicy
	inherited by the continued ladder

Public Types inherited from peclet::amr::MgStage< Dim, Bits >
using	Octree = BlockOctree< Dim, Bits >
	a level's cells on one block

using	Decomposition = core::decomp::BlockDecomposer< Dim >
	the target partition's type

Public Member Functions
void	build (const DO &d, const Vec< Dim > &h0, const Poisson &ap, Index n, const core::decomp::StageTarget< Dim > &target, int id, Index bottomExtent, const Policy &policy, typename Multigrid< Dim, Bits >::Bottom bottom, bool removeMean)
	Build the stage from the level it fires at (`d`, `ap`, `n` as for `ReplicatedTailStage`) onto `target`, a `SiblingMerge` or `Repartition` result of `chooseStageTarget` on `d.decomposition()`.

const char *	kind () const override
	`"replicated"` \| `"sibling"` \| `"repartition"`.

const char *	diagnosticSuffix () const override
	What `pressure_mg_bottom` appends for this stage — `"+tail"` for the replicated one, which is the spelling docs/amr_mg_depth.md §6.7 fixes.

const Decomposition &	targetDecomposition () const override
	The decomposition of the moved level's grid this stage targets.

MPI_Comm	targetComm () const override
	The communicator every collective of the continued ladder runs on.

bool	active () const override
	Whether THIS rank owns a target block, i.e.

const Octree &	targetOctree () const override
	The moved level's cells on this rank's target block.

std::size_t	numLevels () const override
	Levels of the continued ladder, its level 0 (the moved level) included. Local.

Index	numLeaves (std::size_t L) const override
	Cells of continued-ladder level `L` on this rank's target block — the GLOBAL count for the replicated stage, whose one block is the whole level.

std::string	bottomName () const override
	`"jacobi"` \| `"amg"`: what solves the continued ladder's coarsest level, WITHOUT the stage's `diagnosticSuffix()` (the owner appends it).

void	setRemoveMean (bool on) override
	Per-level constant-nullspace projection for the singular periodic pressure; the owner forwards its own flag (`DistributedFlowMultigrid::setRemoveMean`).

void	setBottom (typename Multigrid< Dim, Bits >::Bottom b) override
	Collective on the PARENT communicator (it re-publishes the continued ladder's shape, which a bottom change may alter by building or dropping the continuation's own stage).

View< double >	targetX () override
	The continued ladder's level-0 solution — what `moveDown` reads.

MG &	multigrid ()
	The continued ladder (active ranks only).

void	moveUp (View< const double > src, Index nSrc) override
	`src` (this rank's rows of the moved level, device; may be longer than `nSrc`) → the target's level-0 rhs.

void	cycle (int pre, int post, int bottom, double omega) override
	One cycle of the continued ladder on `targetComm()`. Called on active ranks only.

void	moveDown (View< double > dst, Index nDst) override
	The target's level-0 solution → the first `nDst` rows of `dst`.

Public Member Functions inherited from peclet::amr::MgStage< Dim, Bits >
virtual	~MgStage ()=default

void	apply (View< const double > residual, View< double > correction, Index n, int pre, int post, int bottom, double omega)
	The whole stage for one V-cycle, in the CORRECTION SCHEME §6.5 prescribes: the caller hands in the residual at resolution L and gets back a correction to ADD.

Detailed Description

template<int Dim, unsigned Bits>
class peclet::amr::DistributedStage< Dim, Bits >

A SIBLING-MERGE or REPARTITION stage (docs/amr_mg_depth.md §5.6, WO4b; docs/amr_mg_core_boundary.md §5): the moved level lands on a decomposition of its own grid on FEWER ranks — agglomerated(d) for a sibling merge, a fresh proportional ORB on the first np_L ranks for a repartition, both chosen by core's chooseStageTarget — and the ladder continues there as a DistributedFlowMultigrid on the stage's sub-communicator, with its own lockstep lifts, its own halos and, where it blocks again, its own stage.

Everything that moves is core's: makeStageComm for the communicators, one RedistributeTopology for the level's rows (group Gatherv/Scatterv for a sibling merge, a planned Isend/Irecv over the box intersections for a repartition). What stays here is what a level IS on the target — the octree (DistributedOctree::initDecomposed), its α rows carried over from the moved level rather than re-sampled, and the continued ladder built from them (DistributedFlowMultigrid::buildRaw).

Ranks that own no target block take part in the movement on the parent communicator and skip the recursion; they report the continued ladder's LEVEL COUNT and bottom (broadcast from parent rank 0, which always owns target block 0) and zero cells on every level.

Definition at line 723 of file distributed_flow_mg.hpp.

Member Typedef Documentation

◆ Base

template<int Dim, unsigned Bits>

using peclet::amr::DistributedStage< Dim, Bits >::Base = MgStage<Dim, Bits>

the stage interface

Definition at line 725 of file distributed_flow_mg.hpp.

◆ Octree

template<int Dim, unsigned Bits>

using peclet::amr::DistributedStage< Dim, Bits >::Octree = typename Base::Octree

a level's cells on one block

Definition at line 726 of file distributed_flow_mg.hpp.

◆ Decomposition

template<int Dim, unsigned Bits>

using peclet::amr::DistributedStage< Dim, Bits >::Decomposition = typename Base::Decomposition

the target partition's type

Definition at line 727 of file distributed_flow_mg.hpp.

◆ DO

template<int Dim, unsigned Bits>

using peclet::amr::DistributedStage< Dim, Bits >::DO = DistributedOctree<Dim, Bits>

the level the stage fires at

Definition at line 728 of file distributed_flow_mg.hpp.

◆ Poisson

template<int Dim, unsigned Bits>

using peclet::amr::DistributedStage< Dim, Bits >::Poisson = AmrPoisson<Dim, Bits>

that level's FV operator

Definition at line 729 of file distributed_flow_mg.hpp.

◆ MG

template<int Dim, unsigned Bits>

using peclet::amr::DistributedStage< Dim, Bits >::MG = DistributedFlowMultigrid<Dim, Bits>

the continued ladder

Definition at line 730 of file distributed_flow_mg.hpp.

◆ Policy

template<int Dim, unsigned Bits>

using peclet::amr::DistributedStage< Dim, Bits >::Policy = typename MG::StagePolicy

inherited by the continued ladder

Definition at line 731 of file distributed_flow_mg.hpp.

Member Function Documentation

◆ build()

template<int Dim, unsigned Bits>

void peclet::amr::DistributedStage< Dim, Bits >::build	(	const DO &	d,
		const Vec< Dim > &	h0,
		const Poisson &	ap,
		Index	n,
		const core::decomp::StageTarget< Dim > &	target,
		int	id,
		Index	bottomExtent,
		const Policy &	policy,
		typename Multigrid< Dim, Bits >::Bottom	bottom,
		bool	removeMean
	)

inline

Build the stage from the level it fires at (d, ap, n as for ReplicatedTailStage) onto target, a SiblingMerge or Repartition result of chooseStageTarget on d.decomposition().

id is the per-topology tag offset core's point-to-point movement needs (in [0, RedistributeTopology::kTagSpan)). The continued ladder inherits policy, bottom and removeMean. Collective on d.comm().

Exceptions

std::runtime_error if an axis is not periodic or this rank's leaves are not the root cells of its block (the lift is not nested) — before any communication; core's makeStageComm / RedistributeTopology::build throw on a malformed target.

Definition at line 742 of file distributed_flow_mg.hpp.

◆ kind()

template<int Dim, unsigned Bits>

const char * peclet::amr::DistributedStage< Dim, Bits >::kind ( ) const

inlineoverridevirtual

"replicated" | "sibling" | "repartition".

Implements peclet::amr::MgStage< Dim, Bits >.

Definition at line 824 of file distributed_flow_mg.hpp.

◆ diagnosticSuffix()

template<int Dim, unsigned Bits>

const char * peclet::amr::DistributedStage< Dim, Bits >::diagnosticSuffix ( ) const

inlineoverridevirtual

What pressure_mg_bottom appends for this stage — "+tail" for the replicated one, which is the spelling docs/amr_mg_depth.md §6.7 fixes.

Implements peclet::amr::MgStage< Dim, Bits >.

Definition at line 827 of file distributed_flow_mg.hpp.

◆ targetDecomposition()

template<int Dim, unsigned Bits>

const Decomposition & peclet::amr::DistributedStage< Dim, Bits >::targetDecomposition ( ) const

inlineoverridevirtual

The decomposition of the moved level's grid this stage targets.

Implements peclet::amr::MgStage< Dim, Bits >.

Definition at line 830 of file distributed_flow_mg.hpp.

◆ targetComm()

template<int Dim, unsigned Bits>

MPI_Comm peclet::amr::DistributedStage< Dim, Bits >::targetComm ( ) const

inlineoverridevirtual

The communicator every collective of the continued ladder runs on.

Implements peclet::amr::MgStage< Dim, Bits >.

Definition at line 831 of file distributed_flow_mg.hpp.

◆ active()

template<int Dim, unsigned Bits>

bool peclet::amr::DistributedStage< Dim, Bits >::active ( ) const

inlineoverridevirtual

Whether THIS rank owns a target block, i.e.

takes part in the continued ladder. Ranks that do not still take part in the MOVEMENT, on the parent communicator, and skip the recursion.

Implements peclet::amr::MgStage< Dim, Bits >.

Definition at line 832 of file distributed_flow_mg.hpp.

◆ targetOctree()

template<int Dim, unsigned Bits>

const Octree & peclet::amr::DistributedStage< Dim, Bits >::targetOctree ( ) const

inlineoverridevirtual

The moved level's cells on this rank's target block.

Implements peclet::amr::MgStage< Dim, Bits >.

Definition at line 833 of file distributed_flow_mg.hpp.

References peclet::amr::DistributedOctree< Dim, Bits >::local().

◆ numLevels()

template<int Dim, unsigned Bits>

std::size_t peclet::amr::DistributedStage< Dim, Bits >::numLevels ( ) const

inlineoverridevirtual

Levels of the continued ladder, its level 0 (the moved level) included. Local.

Implements peclet::amr::MgStage< Dim, Bits >.

Definition at line 835 of file distributed_flow_mg.hpp.

◆ numLeaves()

template<int Dim, unsigned Bits>

Index peclet::amr::DistributedStage< Dim, Bits >::numLeaves ( std::size_t L ) const

inlineoverridevirtual

Cells of continued-ladder level L on this rank's target block — the GLOBAL count for the replicated stage, whose one block is the whole level.

Local.

Implements peclet::amr::MgStage< Dim, Bits >.

Definition at line 836 of file distributed_flow_mg.hpp.

References peclet::amr::transferFieldGradients().

◆ bottomName()

template<int Dim, unsigned Bits>

std::string peclet::amr::DistributedStage< Dim, Bits >::bottomName ( ) const

inlineoverridevirtual

"jacobi" | "amg": what solves the continued ladder's coarsest level, WITHOUT the stage's diagnosticSuffix() (the owner appends it).

Local.

Implements peclet::amr::MgStage< Dim, Bits >.

Definition at line 842 of file distributed_flow_mg.hpp.

◆ setRemoveMean()

template<int Dim, unsigned Bits>

void peclet::amr::DistributedStage< Dim, Bits >::setRemoveMean ( bool on )

inlineoverridevirtual

Per-level constant-nullspace projection for the singular periodic pressure; the owner forwards its own flag (DistributedFlowMultigrid::setRemoveMean).

Local.

Implements peclet::amr::MgStage< Dim, Bits >.

Definition at line 843 of file distributed_flow_mg.hpp.

◆ setBottom()

template<int Dim, unsigned Bits>

void peclet::amr::DistributedStage< Dim, Bits >::setBottom ( typename Multigrid< Dim, Bits >::Bottom b )

inlineoverridevirtual

Collective on the PARENT communicator (it re-publishes the continued ladder's shape, which a bottom change may alter by building or dropping the continuation's own stage).

Implements peclet::amr::MgStage< Dim, Bits >.

Definition at line 849 of file distributed_flow_mg.hpp.

◆ targetX()

template<int Dim, unsigned Bits>

View< double > peclet::amr::DistributedStage< Dim, Bits >::targetX ( )

inlineoverridevirtual

The continued ladder's level-0 solution — what moveDown reads.

A test uses it to assert the stage produced the same answer everywhere it is replicated (§11.2).

Implements peclet::amr::MgStage< Dim, Bits >.

Definition at line 854 of file distributed_flow_mg.hpp.

References peclet::amr::transferFieldGradients().

◆ multigrid()

template<int Dim, unsigned Bits>

MG & peclet::amr::DistributedStage< Dim, Bits >::multigrid ( )

inline

The continued ladder (active ranks only).

Precondition: active().

Definition at line 857 of file distributed_flow_mg.hpp.

◆ moveUp()

template<int Dim, unsigned Bits>

void peclet::amr::DistributedStage< Dim, Bits >::moveUp	(	View< const double >	src,
		Index	nSrc
	)

inlineoverridevirtual

src (this rank's rows of the moved level, device; may be longer than nSrc) → the target's level-0 rhs.

Collective on the PARENT communicator: every rank takes part, active or not.

Implements peclet::amr::MgStage< Dim, Bits >.

Definition at line 859 of file distributed_flow_mg.hpp.

References peclet::amr::transferFieldGradients().

◆ cycle()

template<int Dim, unsigned Bits>

void peclet::amr::DistributedStage< Dim, Bits >::cycle	(	int	pre,
		int	post,
		int	bottom,
		double	omega
	)

inlineoverridevirtual

One cycle of the continued ladder on targetComm(). Called on active ranks only.

Implements peclet::amr::MgStage< Dim, Bits >.

Definition at line 877 of file distributed_flow_mg.hpp.

References peclet::amr::transferFieldGradients().

◆ moveDown()

template<int Dim, unsigned Bits>

void peclet::amr::DistributedStage< Dim, Bits >::moveDown	(	View< double >	dst,
		Index	nDst
	)

inlineoverridevirtual

The target's level-0 solution → the first nDst rows of dst.

Implements peclet::amr::MgStage< Dim, Bits >.

Definition at line 881 of file distributed_flow_mg.hpp.

References peclet::amr::transferFieldGradients().

The documentation for this class was generated from the following file:

distributed_flow_mg.hpp

Public Types

Public Member Functions

Detailed Description

Member Typedef Documentation

◆ Base

◆ Octree

◆ Decomposition

◆ DO

◆ Poisson

◆ MG

◆ Policy

Member Function Documentation

◆ build()

◆ kind()

◆ diagnosticSuffix()

◆ targetDecomposition()

◆ targetComm()

◆ active()

◆ targetOctree()

◆ numLevels()

◆ numLeaves()

◆ bottomName()

◆ setRemoveMean()

◆ setBottom()

◆ targetX()

◆ multigrid()

◆ moveUp()

◆ cycle()

◆ moveDown()