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/*
* CartDecomposition.hpp
*
* Created on: Aug 15, 2014
* Author: Pietro Incardona
*/
#ifndef CARTDECOMPOSITION_HPP
#define CARTDECOMPOSITION_HPP
#include "config.h"
#include "Decomposition.hpp"
#include <vector>
#include "global_const.hpp"
#include <initializer_list>
#include "SubdomainGraphNodes.hpp"
#include "metis_util.hpp"
#include "dec_optimizer.hpp"
#include "Space/Shape/Box.hpp"
#include <unordered_map>
#include "NN/CellList/CellList.hpp"
template<unsigned int dim, typename T> using Ghost = Box<dim,T>;
/**
* \brief This class decompose a space into subspaces
*
* This class decompose a space into regular hyper-cube subspaces, and give the possibilities to
* select one subspace
*
* \tparam dim is the dimensionality of the physical domain we are going to decompose.
* \tparam T type of the space we decompose, Real, Integer, Complex ...
* \tparam layout to use
* \tparam Memory Memory factory used to allocate memory
* \tparam Domain Structure that contain the information of your physical domain
* \tparam data type of structure that store the sub-domain decomposition can be an openfpm structure like
* vector, ...
*
* \note if PARALLEL_DECOMPOSITION macro is defined a parallel decomposition algorithm is used, basically
* each processor does not recompute the same decomposition
*
* \note sub-sub-domain portion of space at finer level than the sub-domain (before optimization)
* (or before sub-sub-domain merging)
* \note sub-domain portion of space (after optimization)
* \note near processor sub-domain a sub-domain that live in the a near (or contiguous) processor
*
template<unsigned int dim, typename T, template<typename> class device_l=openfpm::device_cpu, typename Memory=HeapMemory, template<unsigned int, typename> class Domain=Box, template<typename, typename, typename, typename, unsigned int> class data_s = openfpm::vector>
struct Box_proc
{
// Intersection between the local sub-domain enlarged by the ghost and the contiguous processor
// sub-domains
openfpm::vector<::Box<dim,T>> bx;
// Intersection between the contiguous processor sub-domain enlarged by the ghost with the
// local sub-domain
openfpm::vector<::Box<dim,T>> nbx;
// processor
size_t proc;
};
//! Type of the domain we are going to decompose
typedef T domain_type;
//! It simplify to access the SpaceBox element
typedef SpaceBox<dim,T> Box;
private:
//! This is the key type to access data_s, for example in the case of vector
typedef typename data_s<SpaceBox<dim,T>,device_l<SpaceBox<dim,T>>,Memory,openfpm::vector_grow_policy_default,openfpm::vect_isel<SpaceBox<dim,T>>::value >::access_key acc_key;
//! Subspace selected
//! access_key in case of grid is just the set of the index to access the grid
std::vector<acc_key> id_sub;
//! the margin of the sub-domain selected
SpaceBox<dim,T> sub_domain;
//! the set of all local sub-domain as vector
data_s<SpaceBox<dim,T>,device_l<SpaceBox<dim,T>>,Memory,openfpm::vector_grow_policy_default, openfpm::vect_isel<SpaceBox<dim,T>>::value > sub_domains;
//! List of near processors
openfpm::vector<size_t> nn_processors;
//! for each sub-domain, contain the list of the neighborhood processors
//! and for each processor contain the boxes calculated from the intersection
//! of the sub-domain ghost with the near-by processor sub-domain ()
openfpm::vector< openfpm::vector< Box_proc > > box_nn_processor_int;
//! for each box, contain the list of the neighborhood processors
openfpm::vector<openfpm::vector<long unsigned int> > box_nn_processor;
// for each near-processor store the sub-domain of the near processor
std::unordered_map<size_t,typename openfpm::vector<::Box<dim,T>> > nn_processor_subdomains;
//! Structure that contain for each sub-domain box the processor id
//! exist for efficient global communication
//! Structure that store the cartesian grid information
grid_sm<dim,void> gr;
//! Structure that decompose your structure into cell without creating them
//! useful to convert positions to CellId or sub-domain id in this case
CellDecomposer_sm<dim,T> cd;
//! rectangular domain to decompose
Domain<dim,T> domain;
//! Ghost boxes of the processor
//! for each Sub-domain it store the ghost boxes, or
//! the set of boxes that enclose the the ghost space
//! Box cannot overlap, they contain one id that is the
//! processor the information should come from
openfpm::vector< openfpm::vector<Domain<dim,T>> > gh_dom;
//! Internal boxes of the processor
//! for each Sub-domain it store the boxes enclosing the
//! space that must be communicated when another processor
//! require the ghost
//! Box can overlap, they contain one id that is the
//! processor the information should be communicated to
openfpm::vector< openfpm::vector< Domain<dim,T>> > int_box;
//! Box Spacing
T spacing[dim];
//! Runtime virtual cluster machine
Vcluster & v_cl;
//! Structure that store the geometrical information about intersection between the local sub-domain
//! and the near processor sub-domains
CellList<dim,T,FAST> geo_cell;
/*! \brief Enlarge the ghost domain
*
* \param the box
* \param gh spacing of the margin to enlarge
*
*/
void enlarge(::Box<dim,T> & box, Ghost<dim,T> & gh)
{
typedef ::Box<dim,T> g;
for (size_t j = 0 ; j < dim ; j++)
{
box.template getBase<g::p1>(j) = box.template getBase<g::p1>(j) - gh.template getBase<g::p1>(j);
box.template getBase<g::p2>(j) = box.template getBase<g::p2>(j) + gh.template getBase<g::p2>(j);
}
}
/*! \brief Create internally the decomposition
*
* \param v_cl Virtual cluster, used internally to handle or pipeline communication
*
*/
void CreateDecomposition(Vcluster & v_cl)
{
// Calculate the total number of box and and the spacing
// on each direction
// Get the box containing the domain
SpaceBox<dim,T> bs = domain.getBox();
for (unsigned int i = 0; i < dim ; i++)
{
// Calculate the spacing
spacing[i] = (bs.getHigh(i) - bs.getLow(i)) / gr.size(i);
}
// Here we use METIS
// Create a cartesian grid graph
CartesianGraphFactory<dim,Graph_CSR<nm_part_v,nm_part_e>> g_factory_part;
Graph_CSR<nm_part_v,nm_part_e> gp = g_factory_part.template construct<NO_EDGE,T,dim-1>(gr.getSize(),domain);
// Get the number of processing units
size_t Np = v_cl.getProcessingUnits();
// Get the processor id
long int p_id = v_cl.getProcessUnitID();
// Convert the graph to metis
Metis<Graph_CSR<nm_part_v,nm_part_e>> met(gp,Np);
// fill the structure that store the processor id for each sub-domain
// Optimize the decomposition creating bigger spaces
// And reducing Ghost over-stress
dec_optimizer<dim,Graph_CSR<nm_part_v,nm_part_e>> d_o(gp,gr.getSize());
// set of Boxes produced by the decomposition optimizer
openfpm::vector<::Box<dim,size_t>> loc_box;
d_o.template optimize<nm_part_v::sub_id,nm_part_v::id>(gp,p_id,loc_box,box_nn_processor);
// produce the list of the contiguous processor
for (size_t i = 0 ; i < box_nn_processor.size() ; i++)
{
for (size_t j = 0 ; j < box_nn_processor.get(i).size() ; j++)
{
nn_processors.add(box_nn_processor.get(i).get(j));
}
}
// make the list sorted and unique
std::sort(nn_processors.begin(), nn_processors.end());
auto last = std::unique(nn_processors.begin(), nn_processors.end());
nn_processors.erase(last, nn_processors.end());
// convert into sub-domain
for (size_t s = 0 ; s < loc_box.size() ; s++)
{
SpaceBox<dim,T> sub_d(loc_box.get(s));
// add the sub-domain
sub_domains.add(sub_d);
}
// fine_s structure contain the processor id for each sub-sub-domain
// with sub-sub-domain we mean the sub-domain decomposition before
// running dec_optimizer (before merging sub-domains)
auto it = gp.getVertexIterator();
while (it.isNext())
{
size_t key = it.get();
// fill with the fine decomposition
fine_s.get(key) = gp.template vertex_p<nm_part_v::id>(key);
++it;
}
}
/*! \brief Create the subspaces that decompose your domain
*
* Create the subspaces that decompose your domain
*
*/
void CreateSubspaces()
{
// Create a grid where each point is a space
grid_sm<dim,void> g(div);
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// create a grid_key_dx iterator
grid_key_dx_iterator<dim> gk_it(g);
// Divide the space into subspaces
while (gk_it.isNext())
{
//! iterate through all subspaces
grid_key_dx<dim> key = gk_it.get();
//! Create a new subspace
SpaceBox<dim,T> tmp;
//! fill with the Margin of the box
for (int i = 0 ; i < dim ; i++)
{
tmp.setHigh(i,(key.get(i)+1)*spacing[i]);
tmp.setLow(i,key.get(i)*spacing[i]);
}
//! add the space box
sub_domains.add(tmp);
// add the iterator
++gk_it;
}
}
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// Heap memory receiver
HeapMemory hp_recv;
// vector v_proc
openfpm::vector<size_t> v_proc;
// Receive counter
size_t recv_cnt;
/*! \brief Message allocation
*
* \param message size required to receive from i
* \param total message size to receive from all the processors
* \param the total number of processor want to communicate with you
* \param i processor id
* \param ptr a pointer to the vector_dist structure
*
* \return the pointer where to store the message
*
*/
static void * message_alloc(size_t msg_i ,size_t total_msg, size_t total_p, size_t i, void * ptr)
{
// cast the pointer
CartDecomposition<dim,T,device_l,Memory,Domain,data_s> * cd = static_cast< CartDecomposition<dim,T,device_l,Memory,Domain,data_s> *>(ptr);
// Resize the memory
cd->nn_processor_subdomains[i].resize(msg_i);
// Return the receive pointer
return cd->nn_processor_subdomains[i].getPointer();
}
public:
/*! \brief Cartesian decomposition copy constructor
*
* \param v_cl Virtual cluster, used internally to handle or pipeline communication
*
*/
CartDecomposition(CartDecomposition<dim,T,device_l,Memory,Domain,data_s> && cd)
:sub_domain(cd.sub_domain),gr(cd.gr),cd(cd.cd),domain(cd.domain),v_cl(cd.v_cl)
{
//! Subspace selected
//! access_key in case of grid is just the set of the index to access the grid
id_sub.swap(cd.id_sub);
//! the set of all local sub-domain as vector
sub_domains.swap(cd.sub_domains);
for (int i = 0 ; i < dim ; i++)
{
//! Box Spacing
this->spacing[i] = spacing[i];
}
}
/*! \brief Cartesian decomposition constructor
*
* \param v_cl Virtual cluster, used internally to handle or pipeline communication
*
*/
CartDecomposition(Vcluster & v_cl)
{}
/*! \brief Cartesian decomposition constructor, it divide the space in boxes
*
* \param dec is a vector that store how to divide on each dimension
* \param domain is the domain to divide
* \param v_cl are information of the cluster runtime machine
*
*/
CartDecomposition(std::vector<size_t> dec, Domain<dim,T> domain, Vcluster & v_cl)
:id_sub(0),gr(dec),cd(domain,dec),domain(domain),v_cl(v_cl)
{
// Create the decomposition
CreateDecomposition(v_cl);
}
//! Cartesian decomposition destructor
~CartDecomposition()
{}
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/*! It calculate the ghost boxes and internal boxes
*
* Example: Processor 10 calculate
* B8_0 B9_0 B9_1 and B5_0
*
*
+----------------------------------------------------+
| |
| Processor 8 |
| Sub-domain 0 +-----------------------------------+
| | |
| | |
++--------------+---+---------------------------+----+ Processor 9 |
| | | B8_0 | | Subdomain 0 |
| +------------------------------------+ |
| | | | | |
| | | XXXXXXXXXXXXX XX |B9_0| |
| | B | X Processor 10 X | | |
| Processor 5 | 5 | X Sub-domain 0 X | | |
| Subdomain 0 | _ | X X +----------------------------------------+
| | 0 | XXXXXXXXXXXXXXXX | | |
| | | | | |
| | | | | Processor 9 |
| | | |B9_1| Subdomain 1 |
| | | | | |
| | | | | |
| | | | | |
+--------------+---+---------------------------+----+ |
| |
+-----------------------------------+
and also
G8_0 G9_0 G9_1 G5_0
+----------------------------------------------------+
| |
| Processor 8 |
| Sub-domain 0 +-----------------------------------+
| +---------------------------------------------+ |
| | G8_0 | | |
++--------------+------------------------------------+ | Processor 9 |
| | | | | Subdomain 0 |
| | | |G9_0| |
| | | | | |
| | | XXXXXXXXXXXXX XX | | |
| | | X Processor 10 X | | |
| Processor|5 | X Sub-domain 0 X | | |
| Subdomain|0 | X X +-----------------------------------+
| | | XXXXXXXXXXXXXXXX | | |
| | G | | | |
| | 5 | | | Processor 9 |
| | | | | | Subdomain 1 |
| | 0 | |G9_1| |
| | | | | |
| | | | | |
+--------------+------------------------------------+ | |
| | | |
+----------------------------------------+----+------------------------------+
*
*
*
* \param ghost margins for each dimensions (p1 negative part) (p2 positive part)
*
^ p2[1]
|
|
+----+----+
| |
| |
p1[0]<-----+ +----> p2[0]
| |
| |
+----+----+
|
v p1[1]
*
*
*/
void calculateGhostBoxes(Ghost<dim,T> & ghost)
{
typedef Ghost<dim,T> g;
#ifdef DEBUG
// the ghost margins are assumed to be smaller
// than one sub-domain
for (size_t i = 0 ; i < dim ; i++)
{
if (ghost.template getBase<g::p1>() >= domain.template getBase<g::p1>() / gr.size(i) )
{
std::cerr << "Error: Ghost are bigger that one domain" << "\n";
}
}
#endif
// create a buffer with the sub-domain of this processors, the informations ( the box )
// of sub-domain contiguous to the processor A are sent to the processor A and
// the information of the contiguous sub-domains in the near processors are received
//
openfpm::vector< openfpm::vector< ::Box<dim,T>> > boxes(nn_processors.size());
// create the sub-domain buffer information to send
openfpm::vector< size_t > prc;
for (size_t b = 0 ; b < box_nn_processor.size() ; b++)
{
for (size_t p = 0 ; p < box_nn_processor.get(b).size() ; p++)
{
size_t prc = box_nn_processor.get(b).get(p);
boxes.add(sub_domains.get(b));
}
}
// Intersect all the local sub-domains with the sub-domains of the contiguous processors
// Get the sub-domains of the near processors
v_cl.sendrecvMultipleMessages(boxes,prc,CartDecomposition<dim,T,device_l,Memory,Domain,data_s>::message_alloc, this ,NEED_ALL_SIZE);
box_nn_processor_int.resize(box_nn_processor.size());
// For each sub-domain
for (size_t i = 0 ; i < sub_domains.size() ; i++)
{
::Box<dim,size_t> sub_with_ghost = sub_domains.get(i);
// enlarge the sub-domain with the ghost
enlarge(sub_with_ghost,ghost);
// For each processor contiguous to this sub-domain
for (size_t j = 0 ; j < box_nn_processor.get(i).size() ; j++)
{
// Contiguous processor
size_t p_id = box_nn_processor.get(i).get(j);
// get the set of sub-domains of the contiguous processor p_id
openfpm::vector< ::Box<dim,T> > & p_box = nn_processor_subdomains[p_id];
// near processor sub-domain intersections
openfpm::vector< ::Box<dim,T> > & p_box_int = box_nn_processor_int.get(i).get(j).bx;
// for each near processor sub-domain intersect with the enlarged local sub-domain and store it
for (size_t b = 0 ; b < p_box.size() ; b++)
{
bool intersect;
::Box<dim,T> bi = sub_with_ghost.Intersect(p_box.get(b),intersect);
if (intersect == true)
p_box_int.add(bi);
}
}
// For each processor contiguous to this sub-domain
for (size_t j = 0 ; j < box_nn_processor.get(i).size() ; j++)
{
// Contiguous processor
size_t p_id = box_nn_processor.get(i).get(j);
// get the set of sub-domains of the contiguous processor p_id
openfpm::vector< ::Box<dim,T> > & nn_p_box = nn_processor_subdomains[p_id];
// near processor sub-domain intersections
openfpm::vector< ::Box<dim,T> > & p_box_int = box_nn_processor_int.get(i).get(j).bbx;
// For each near processor sub-domains enlarge and intersect with the local sub-domain and store the result
for (size_t k = 0 ; k < nn_p_box.size() ; k++)
{
// enlarge the local sub-domain
::Box<dim,T> n_sub = nn_p_box.get(k);
// Create a margin of ghost size around the near processor sub-domain
elarge(n_sub,ghost);
// Intersect with the local sub-domain
bool intersect;
::Box<dim,T> b_int = n_sub.Intersect(n_sub,intersect);
// store if it intersect
if (intersect == true)
{
typedef ::Box<dim,T> b;
p_box_int.add(b_int);
// update the geo_cell list
// get the boxes this box span
grid_key<dim> p1 = geo_cell.getCell(b_int.template get<b::p1>() );
grid_key<dim> p2 = geo_cell.getCell(b_int.template get<b::p2>() );
// Get the grid and the sub-iterator
auto & gi = geo_cell.getGrid();
grid_key_dx_iterator_sub<dim> g_sub(gi,p1,p2);
// add the box-id to the cell list
while (g_sub.isNext())
{
auto & key = g_sub.get();
geo_cell.add(gi.LinId(key),p_box_int.size()-1);
++g_sub;
}
}
}
}
}
}
/*! \brief processorID return in which processor the particle should go
*
* \return processorID
*
*/
template<typename Mem> size_t inline processorID(encapc<1, Point<dim,T>, Mem> p)
}
/*! \brief processorID return in which processor the particle should go
*
* \return processorID
*
*/
size_t inline processorID(T (&p)[dim])
{
/*! \brief Set the parameter of the decomposition
*
* \param div_ std::vector storing into how many domain to decompose on each dimension
* \param domain_ domain to decompose
*
*/
void setParameters(std::vector<size_t> div_, Domain<dim,T> domain_)
{
// Set the decomposition parameters
div = div_;
domain = domain_;
//! Create the decomposition
CreateDecomposition(v_cl);
}
/*! \brief Set the parameter of the decomposition
*
* \param div_ std::vector storing into how many domain to decompose on each dimension
* \param domain_ domain to decompose
*
*/
void setParameters(const size_t (& div_)[dim], Domain<dim,T> domain_)
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//! Create the decomposition
CreateDecomposition(v_cl);
}
/*! \brief Get the number of local local hyper-cubes or sub-domains
*
* \return the number of sub-domains
*
*/
size_t getNLocalHyperCube()
{
return sub_domains.size();
}
/*! The the bulk part of the data set, or the data that
* does not depend from the ghosts layers
*
* \return the bulk of your data
*
*/
T getBulk()
{
}
/*! \brief This function divide the data set into bulk, border, external and internal part
*
* \tparam dim dimensionality of the structure storing your data
* (example if they are in 3D grid, has to be 3)
* \tparam T type of object we are dividing
* \tparam device type of layout selected
* \param data 1-dimensional grid of point
* \param nb define the neighborhood of all the points
* \return a structure with the set of objects divided
*
*/
// dataDiv<T> CartDecomposition<dim,T,layout>::divide(layout::grid<1,Point<dim,T>> & data, neighborhood & nb);
/*! The the internal part of the data set, or the data that
* are inside the local space
*
* \return the internal part of your data
*
*/
T getInternal()
{
}
/*! Get the internal part of the dataset, or the data that
* depend from the ghost layers
*
* \return the ghost part of your data
*
*/
T getBorder()
{
}
/*! Get the external part of the dataset, or the data that
* are outside localSpace including ghost
*
* \return the external part of your data
*
*/
T getExternal()
{
}
/*! \brief Get the number of one set of hyper-cube enclosing one particular
* subspace, the hyper-cube enclose your space, even if one box is enough
* can be more that one to increase occupancy
*
* In case of Cartesian decomposition it just return 1, each subspace
* has one hyper-cube, and occupancy 1
*
* \param id of the subspace
* \return the number of hyper-cube enclosing your space
*
*/
size_t getNHyperCube(size_t id)
{
return 1;
}
/*! \brief Get the hyper-cube margins id_c has to be 0
*
* Get the hyper-cube margins id_c has to be 0, each subspace
* has one hyper-cube
*
* \param id of the subspace
* \param id_c
* \return The specified hyper-cube space
*
*/
SpaceBox<dim,T> & getHyperCubeMargins(size_t id, size_t id_c)
{
#ifdef DEBUG
// Check if this subspace exist
{
std::cerr << "Error CartDecomposition: id > N_tot";
}
else if (id_c > 0)
{
// Each subspace is an hyper-cube so return error if id_c > 0
std::cerr << "Error CartDecomposition: id_c > 0";
}
#endif
return sub_domains.get<Object>(id);
}
/*! \brief Get the total number of Hyper-cube
*
* Get the total number of Hyper-cube
*
* \return The total number of hyper-cube
*
*/
size_t getNHyperCube()
{
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}
/*! \brief produce an hyper-cube approximation of the space decomposition
*
*/
void hyperCube()
{
}
/*! \brief Select the local space
*
* Select the local space
*
* \param sub select the sub-space
*
*/
void setSpace(size_t sub)
{
id_sub.push_back(sub);
}
/*! \brief Get the local grids
*
* Get the local grids
*
* \return the local grids
*
*/
auto getLocalHyperCubes() -> decltype(sub_domains) &
{
return sub_domains;
}
/*! \brief Get the local hyper-cubes
*
* Get the local hyper-cubes
*
* \param lc is the id of the space
* \return the local hyper-cube
*
*/
SpaceBox<dim,T> getLocalHyperCube(size_t lc)
{
// Create a space box
SpaceBox<dim,T> sp;
// fill the space box
for (size_t k = 0 ; k < dim ; k++)
{
// create the SpaceBox Low and High
sp.setLow(k,sub_domains.template get<Box::p1>(lc)[k]);
sp.setHigh(k,sub_domains.template get<Box::p2>(lc)[k]);
}
return sp;
}
/*! \brief Return the structure that store the physical domain
*
* Return the structure that store the physical domain
*
* \return The physical domain
*
*/
Domain<dim,T> & getDomain()
{
return domain;
}
/*! \brief Check if the particle is local
*
* \param p object position
template<typename Mem> bool isLocal(encapc<1, Point<dim,T>, Mem> p)
return processorID<Mem>() == v_cl.getProcessUnitID();
}
return processorID(pos) == v_cl.getProcessUnitID();
}
::Box<dim,T> bbox;
/*! \brief Return the bounding box containing the processor box + smallest subdomain spacing
*
* \return The bounding box
*
*/
::Box<dim,T> & getProcessorBounds()
{
return bbox;
}