portelli/Grid
1
0
Fork 0
mirror of https://github.com/paboyle/Grid.git synced 2026-08-13 14:14:36 +01:00
Code Releases Activity

Check in codes used at time of Lattice conference for PVdagM multigrid

Browse Source
This commit is contained in:
Peter Boyle
2026-08-11 16:35:42 -04:00
parent fb5662a449
commit 5792195073
8 changed files with 6000 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files
examples/Example_pvdagm_4level.cc
+798
View File
@@ -0,0 +1,798 @@
/*************************************************************************************
Grid physics library, www.github.com/paboyle/Grid
Source file: ./examples/Example_pvdagm_3level.cc
Copyright (C) 2023
Author: Peter Boyle <paboyle@ph.ed.ac.uk>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
See the full license in the file "LICENSE" in the top level distribution directory
*************************************************************************************/
/* END LEGAL */
#include <Grid/Grid.h>
#include <Grid/lattice/PaddedCell.h>
#include <Grid/stencil/GeneralLocalStencil.h>
#include <Grid/algorithms/iterative/PrecGeneralisedConjugateResidual.h>
#include <Grid/algorithms/iterative/PrecGeneralisedConjugateResidualNonHermitian.h>
#include <Grid/algorithms/iterative/BiCGSTAB.h>
using namespace std;
using namespace Grid;
template <class T> void readFile(T& out, std::string const fname){
#ifdef HAVE_LIME
std::cout << Grid::GridLogMessage << "Reading: " << fname << std::endl;
Grid::emptyUserRecord record;
Grid::ScidacReader SR;
SR.open(fname);
SR.readScidacFieldRecord(out, record);
SR.close();
#endif
}
template <class T> void writeFile(T& in, std::string const fname){
#ifdef HAVE_LIME
std::cout << Grid::GridLogMessage << "Writing: " << fname << std::endl;
Grid::emptyUserRecord record;
Grid::ScidacWriter SW(in.Grid()->IsBoss());
SW.open(fname);
SW.writeScidacFieldRecord(in, record);
SW.close();
#endif
}
template <class Field>
void saveSubspace(std::vector<Field> &subspace, std::string const fname){
#ifdef HAVE_LIME
std::cout << Grid::GridLogMessage << "Saving subspace (" << subspace.size() << " vectors) to: " << fname << std::endl;
Grid::emptyUserRecord record;
Grid::ScidacWriter SW(subspace[0].Grid()->IsBoss());
SW.open(fname);
for (int k = 0; k < (int)subspace.size(); k++)
SW.writeScidacFieldRecord(subspace[k], record);
SW.close();
#endif
}
template <class Field>
void loadSubspace(std::vector<Field> &subspace, std::string const fname){
#ifdef HAVE_LIME
std::cout << Grid::GridLogMessage << "Loading subspace (" << subspace.size() << " vectors) from: " << fname << std::endl;
Grid::emptyUserRecord record;
Grid::ScidacReader SR;
SR.open(fname);
for (int k = 0; k < (int)subspace.size(); k++)
SR.readScidacFieldRecord(subspace[k], record);
SR.close();
#endif
}
template<class Matrix,class Field>
class PVdagMLinearOperator : public LinearOperatorBase<Field> {
Matrix &_Mat;
Matrix &_PV;
int nApp;
int nAppDag;
public:
PVdagMLinearOperator(Matrix &Mat,Matrix &PV): _Mat(Mat),_PV(PV), nApp(0), nAppDag(0) {};
void OpDiag (const Field &in, Field &out) { assert(0); }
void OpDir (const Field &in, Field &out,int dir,int disp) { assert(0); }
void OpDirAll (const Field &in, std::vector<Field> &out){ assert(0); };
void Op (const Field &in, Field &out){
Field tmp(in.Grid());
_Mat.M(in,tmp);
_PV.Mdag(tmp,out);
nApp++;
}
void AdjOp (const Field &in, Field &out){
Field tmp(in.Grid());
_PV.M(in,tmp);
_Mat.Mdag(tmp,out);
nAppDag++;
}
void clear() { nApp = 0; nAppDag = 0; }
void getApplications() {
std::cout << GridLogMessage << "# applications of PVdagM: " << nApp << std::endl;
std::cout << GridLogMessage << "# applications of PVdagM^dag: " << nAppDag << std::endl;
std::cout << GridLogMessage << "# applications total: " << nApp + nAppDag << std::endl;
}
void HermOpAndNorm(const Field &in, Field &out,RealD &n1,RealD &n2){
HermOp(in,out);
ComplexD dot = innerProduct(in,out);
n1=real(dot);
n2=norm2(out);
}
void HermOp(const Field &in, Field &out){
Field tmp(in.Grid());
Op(in,tmp);
AdjOp(tmp,out);
}
};
template<class Matrix,class Field>
class MdagPVLinearOperator : public LinearOperatorBase<Field> {
Matrix &_Mat;
Matrix &_PV;
public:
MdagPVLinearOperator(Matrix &Mat,Matrix &PV): _Mat(Mat),_PV(PV){};
void OpDiag (const Field &in, Field &out) { assert(0); }
void OpDir (const Field &in, Field &out,int dir,int disp) { assert(0); }
void OpDirAll (const Field &in, std::vector<Field> &out){ assert(0); };
void Op (const Field &in, Field &out){
Field tmp(in.Grid());
_PV.M(in,tmp);
_Mat.Mdag(tmp,out);
}
void AdjOp (const Field &in, Field &out){
Field tmp(in.Grid());
_Mat.M(in,tmp);
_PV.Mdag(tmp,out);
}
void HermOpAndNorm(const Field &in, Field &out,RealD &n1,RealD &n2){
ComplexD dot = innerProduct(in,out);
n1=real(dot);
n2=norm2(out);
}
void HermOp(const Field &in, Field &out){
Field tmp(in.Grid());
Op(in,tmp);
AdjOp(tmp,out);
}
};
template<class Matrix,class Field>
class ShiftedPVdagMLinearOperator : public LinearOperatorBase<Field> {
Matrix &_Mat;
Matrix &_PV;
RealD shift;
public:
ShiftedPVdagMLinearOperator(RealD _shift,Matrix &Mat,Matrix &PV): shift(_shift),_Mat(Mat),_PV(PV){};
void OpDiag (const Field &in, Field &out) { assert(0); }
void OpDir (const Field &in, Field &out,int dir,int disp) { assert(0); }
void OpDirAll (const Field &in, std::vector<Field> &out){ assert(0); };
void Op (const Field &in, Field &out){
Field tmp(in.Grid());
_Mat.M(in,tmp);
_PV.Mdag(tmp,out);
out = out + shift * in;
}
void AdjOp (const Field &in, Field &out){
Field tmp(in.Grid());
_PV.M(tmp,out);
_Mat.Mdag(in,tmp);
out = out + shift * in;
}
void HermOpAndNorm(const Field &in, Field &out,RealD &n1,RealD &n2){ assert(0); }
void HermOp(const Field &in, Field &out){
Field tmp(in.Grid());
Op(in,tmp);
AdjOp(tmp,out);
}
};
// Lüscher deflated guesser (arXiv:0706.2298 Sec A.3) for a non-Hermitian solve.
// C_{st} = <psi[s] | LinOp | psi[t]>; guess = sum_s c_s psi[s] where c = C^{-1} psi† src.
template<class Field>
class LuscherGuesser : public LinearFunction<Field> {
const std::vector<Field> &psi;
Eigen::MatrixXcd C_inv;
public:
using LinearFunction<Field>::operator();
LuscherGuesser(const std::vector<Field> &psi_, const Eigen::MatrixXcd &Cinv_)
: psi(psi_), C_inv(Cinv_) {}
virtual void operator()(const Field &src, Field &guess) {
int N = psi.size();
Eigen::VectorXcd b(N);
for (int t = 0; t < N; t++)
b(t) = TensorRemove(innerProduct(psi[t], src));
Eigen::VectorXcd c = C_inv * b;
guess = Zero();
for (int s = 0; s < N; s++)
guess += ComplexD(c(s)) * psi[s];
}
};
template<class Fobj,class CComplex,int nbasis>
class MGPreconditioner : public LinearFunction< Lattice<Fobj> > {
public:
using LinearFunction<Lattice<Fobj> >::operator();
typedef Aggregation<Fobj,CComplex,nbasis> Aggregates;
typedef typename Aggregation<Fobj,CComplex,nbasis>::FineField FineField;
typedef typename Aggregation<Fobj,CComplex,nbasis>::CoarseVector CoarseVector;
typedef typename Aggregation<Fobj,CComplex,nbasis>::CoarseMatrix CoarseMatrix;
typedef LinearOperatorBase<FineField> FineOperator;
typedef LinearFunction <FineField> FineSmoother;
typedef LinearOperatorBase<CoarseVector> CoarseOperator;
typedef LinearFunction <CoarseVector> CoarseSolver;
Aggregates & _Aggregates;
FineOperator & _FineOperator;
FineSmoother & _PreSmoother;
FineSmoother & _PostSmoother;
CoarseOperator & _CoarseOperator;
CoarseSolver & _CoarseSolve;
CoarseSolver & _CoarseGuesser;
int level; void Level(int lv) {level = lv; };
MGPreconditioner(Aggregates &Agg,
FineOperator &Fine,
FineSmoother &PreSmoother,
FineSmoother &PostSmoother,
CoarseOperator &CoarseOperator_,
CoarseSolver &CoarseSolve_,
CoarseSolver &CoarseGuesser_)
: _Aggregates(Agg),
_FineOperator(Fine),
_PreSmoother(PreSmoother),
_PostSmoother(PostSmoother),
_CoarseOperator(CoarseOperator_),
_CoarseSolve(CoarseSolve_),
_CoarseGuesser(CoarseGuesser_),
level(1) { }
virtual void operator()(const FineField &in, FineField & out)
{
GridBase *CoarseGrid = _Aggregates.CoarseGrid;
CoarseVector Csrc(CoarseGrid);
CoarseVector Csol(CoarseGrid);
FineField vec1(in.Grid());
FineField vec2(in.Grid());
double t;
out = Zero();
t=-usecond();
_PreSmoother(in,out);
t+=usecond();
std::cout<<GridLogMessage << "PreSmoother took "<< t/1000.0<< "ms" <<std::endl;
_FineOperator.Op(out,vec1); sub(vec1, in ,vec1);
t=-usecond();
_Aggregates.ProjectToSubspace(Csrc,vec1);
t+=usecond();
std::cout<<GridLogMessage << "Project to coarse took "<< t/1000.0<< "ms" <<std::endl;
t=-usecond();
_CoarseGuesser(Csrc,Csol);
_CoarseSolve(Csrc,Csol);
t+=usecond();
std::cout<<GridLogMessage << "Coarse solve took "<< t/1000.0<< "ms" <<std::endl;
t=-usecond();
_Aggregates.PromoteFromSubspace(Csol,vec1);
add(out,out,vec1);
t+=usecond();
std::cout<<GridLogMessage << "Promote to this level took "<< t/1000.0<< "ms" <<std::endl;
_FineOperator.Op(out,vec1); sub(vec1 ,in , vec1);
t=-usecond();
vec2=Zero();
_PostSmoother(vec1,vec2);
t+=usecond();
std::cout<<GridLogMessage << "PostSmoother took "<< t/1000.0<< "ms" <<std::endl;
add(out,out,vec2);
}
};
// Generic shifted linear operator: wraps any LinearOperatorBase and adds shift*I.
// Used to condition the coarse-level GCR smoother, analogous to ShiftedPVdagMLinearOperator
// at the fine level.
template<class Field>
class ShiftedLinearOperator : public LinearOperatorBase<Field> {
LinearOperatorBase<Field> &_Op;
RealD shift;
public:
ShiftedLinearOperator(RealD _shift, LinearOperatorBase<Field> &Op) : shift(_shift), _Op(Op) {}
void OpDiag (const Field &in, Field &out) { assert(0); }
void OpDir (const Field &in, Field &out, int dir, int disp) { assert(0); }
void OpDirAll (const Field &in, std::vector<Field> &out) { assert(0); }
void Op (const Field &in, Field &out) { _Op.Op(in, out); out = out + shift * in; }
void AdjOp (const Field &in, Field &out) { _Op.AdjOp(in, out); out = out + shift * in; }
void HermOpAndNorm(const Field &in, Field &out, RealD &n1, RealD &n2) { assert(0); }
void HermOp (const Field &in, Field &out) { Field tmp(in.Grid()); Op(in,tmp); AdjOp(tmp,out); }
};
template<int NB, class PVdagM_t, class ShiftedPVdagM_t, class Subspace, class LittleDiracOperator, class CoarseVector, class TwoLevelMG>
void runMG(
GridCartesian *FGrid,
GridCartesian *Coarse5d,
GridCartesian *CoarseCoarse5d,
GridCartesian *CoarseCoarseCoarse5d,
NextToNearestStencilGeometry5D geom,
PVdagM_t &PVdagM,
ShiftedPVdagM_t &ShiftedPVdagM,
Subspace &AggregatesPD
) {
std::vector<LatticeFermion> subspace = AggregatesPD.subspace;
assert((int)subspace.size() == NB);
const int nbasis = NB;
const int cb = 0;
CoarseVector c_src(Coarse5d);
CoarseVector c_res(Coarse5d);
Complex one(1.0);
LatticeFermionD f_src(FGrid);
LatticeFermionD f_res(FGrid);
TrivialPrecon<CoarseVector> simpleC;
TrivialPrecon<LatticeFermionD> simple_fine;
//////////////////////////////////////////////////////////////////////
// Level 0→1: coarsen PVdagM, build LinOpCoarse
//////////////////////////////////////////////////////////////////////
LittleDiracOperator LittleDiracOpPV(geom, FGrid, Coarse5d);
LittleDiracOpPV.CoarsenOperator(PVdagM, AggregatesPD);
NonHermitianLinearOperator<LittleDiracOperator,CoarseVector> LinOpCoarse(LittleDiracOpPV);
//////////////////////////////////////////////////////////////////////
// Baseline: plain PGCR on LinOpCoarse (reference for comparison)
//////////////////////////////////////////////////////////////////////
std::cout<<GridLogMessage<<"*******************************************"<<std::endl;
std::cout<<GridLogMessage<<" Level 1 solve: plain PGCR baseline"<<std::endl;
std::cout<<GridLogMessage<<"*******************************************"<<std::endl;
PrecGeneralisedConjugateResidualNonHermitian<CoarseVector> L2PGCR_baseline(3.0e-2,1100,LinOpCoarse,simpleC,10,10);
L2PGCR_baseline.Level(2);
L2PGCR_baseline.Name("Cbaseline");
c_src = one;
c_res = Zero();
L2PGCR_baseline(c_src,c_res);
//////////////////////////////////////////////////////////////////////
// psi_coarse: coarse projections of pre-GS fine null vectors.
// These are the Level 1 near-null vectors, promoted from Level 0.
// Used as the aggregation basis for Level 1→2 coarsening.
//////////////////////////////////////////////////////////////////////
std::vector<CoarseVector> psi_coarse(nbasis, Coarse5d);
for (int k = 0; k < nbasis; k++)
AggregatesPD.ProjectToSubspace(psi_coarse[k], subspace[k]);
//////////////////////////////////////////////////////////////////////
// Diagnostics: W (fine projected matrix) and C (Galerkin check)
//////////////////////////////////////////////////////////////////////
{
Eigen::MatrixXcd W = Eigen::MatrixXcd::Zero(nbasis, nbasis);
LatticeFermion ftmp(FGrid);
for (int j = 0; j < nbasis; j++) {
PVdagM.Op(subspace[j], ftmp);
for (int i = 0; i < nbasis; i++)
W(i,j) = TensorRemove(innerProduct(subspace[i], ftmp));
}
RealD normW = W.norm();
std::cout << GridLogMessage << "Fine projected matrix ||W|| = " << normW << std::endl;
Eigen::MatrixXcd C = Eigen::MatrixXcd::Zero(nbasis, nbasis);
CoarseVector Ac(Coarse5d);
for (int l = 0; l < nbasis; l++) {
LinOpCoarse.Op(psi_coarse[l], Ac);
for (int k = 0; k < nbasis; k++)
C(k,l) = TensorRemove(innerProduct(psi_coarse[k], Ac));
}
RealD normC = C.norm();
RealD normCmCdag = (C - C.adjoint()).norm();
std::cout << GridLogMessage << "Coarse null matrix ||C|| = " << normC << std::endl;
std::cout << GridLogMessage << "Coarse null matrix ||C - C†||/||C|| = " << normCmCdag/normC << std::endl;
std::cout << GridLogMessage << "Galerkin check ||C||/||W|| = " << normC/normW << std::endl;
}
//////////////////////////////////////////////////////////////////////
// Level 1→2: set up aggregation using psi_coarse as subspace.
// Block factor 2,2,3,2 (removes odd local sublattice in z given MPI
// geometry 3×6×4×4 where z-local at Level 1 is 6).
// psi_coarse are assigned directly; CoarsenOperator performs
// block-GS orthogonalisation before building LinOpCoarseCoarse.
//////////////////////////////////////////////////////////////////////
// innerProduct(CoarseSiteObj, CoarseSiteObj) returns iScalar<vTComplex>, so CComplex
// for the L1→L2 level must be iScalar<vTComplex>, not vTComplex.
typedef typename CoarseVector::vector_object CoarseSiteObj;
typedef iScalar<vTComplex> vTTComplex;
typedef GeneralCoarsenedMatrix<CoarseSiteObj,vTTComplex,NB> LittleDiracOperatorL2;
typedef typename LittleDiracOperatorL2::CoarseVector CoarseCoarseVector;
typedef Aggregation<CoarseSiteObj,vTTComplex,NB> SubspaceL2;
typedef MGPreconditioner<CoarseSiteObj,vTTComplex,NB> L1to2MG;
SubspaceL2 AggregatesL2(CoarseCoarse5d, Coarse5d, cb);
for (int k = 0; k < nbasis; k++)
AggregatesL2.subspace[k] = psi_coarse[k];
NextToNearestStencilGeometry5D geom2(CoarseCoarse5d);
LittleDiracOperatorL2 LittleDiracOpL2(geom2, Coarse5d, CoarseCoarse5d);
LittleDiracOpL2.CoarsenOperator(LinOpCoarse, AggregatesL2);
NonHermitianLinearOperator<LittleDiracOperatorL2,CoarseCoarseVector> LinOpCC(LittleDiracOpL2);
TrivialPrecon<CoarseCoarseVector> simpleCC;
//////////////////////////////////////////////////////////////////////
// Lüscher deflation guesser for L3PGCR.
// Step 1: project psi_coarse[k] (promoted fine null vectors) to
// CoarseCoarseVector space — these cover the zero-momentum
// component of the near-null space of LinOpCC.
// Step 2: breed Nextra additional null vectors directly on LinOpCC
// using GCR with random sources — these pick up near-null
// modes at all spatial frequencies not spanned by step 1.
// Step 3: build C_{st} = <psi_cc[s]|LinOpCC|psi_cc[t]> over the
// full augmented basis and invert directly via Eigen LU.
//////////////////////////////////////////////////////////////////////
std::vector<CoarseCoarseVector> psi_cc(nbasis, CoarseCoarse5d);
for (int k = 0; k < nbasis; k++)
AggregatesL2.ProjectToSubspace(psi_cc[k], psi_coarse[k]);
{
int Nextra = nbasis; // breed as many extra as we have promoted ones
if ( getenv("CC_NEXTRA") ) Nextra = atoi(getenv("CC_NEXTRA"));
GridParallelRNG RNG_CC(CoarseCoarse5d);
RNG_CC.SeedFixedIntegers({11,13,17,19});
PrecGeneralisedConjugateResidualNonHermitian<CoarseCoarseVector>
nullGCR(1e-2, 200, LinOpCC, simpleCC, 32, 32);
CoarseCoarseVector tmp(CoarseCoarse5d);
for (int k = 0; k < Nextra; k++) {
CoarseCoarseVector src(CoarseCoarse5d);
gaussian(RNG_CC, src);
tmp = Zero();
nullGCR(src, tmp);
psi_cc.push_back(tmp);
}
std::cout << GridLogMessage << "LinOpCC deflation basis: " << nbasis
<< " promoted + " << Nextra << " bred = " << psi_cc.size() << " total" << std::endl;
}
const int Naug = psi_cc.size();
Eigen::MatrixXcd Ccc = Eigen::MatrixXcd::Zero(Naug, Naug);
{
CoarseCoarseVector Acc(CoarseCoarse5d);
for (int l = 0; l < Naug; l++) {
LinOpCC.Op(psi_cc[l], Acc);
for (int k = 0; k < Naug; k++)
Ccc(k,l) = TensorRemove(innerProduct(psi_cc[k], Acc));
}
}
{
RealD normCcc = Ccc.norm();
RealD normCccmCdag = (Ccc - Ccc.adjoint()).norm();
std::cout << GridLogMessage << "Coarse-coarse deflation matrix ||Ccc|| = " << normCcc << std::endl;
std::cout << GridLogMessage << "Coarse-coarse deflation matrix ||Ccc-Ccc†||/||Ccc|| = " << normCccmCdag/normCcc << std::endl;
}
Eigen::MatrixXcd Ccc_inv = Ccc.inverse();
LuscherGuesser<CoarseCoarseVector> CCDeflGuesser(psi_cc, Ccc_inv);
//////////////////////////////////////////////////////////////////////
// Level 2→3: coarsen LinOpCC using the RAW promoted psi_cc as aggregation
// to build the Level 4 (coarse-coarse-coarse) operator.
// psi_cc[0..nbasis-1] are the coarse-coarse near-null vectors, projected
// from the RAW psi_coarse (themselves projected from the RAW fine null
// vectors) -- the pre-block-GS chain the whole construction depends on.
// CoarsenOperator block-GS orthogonalises AggregatesL3.subspace IN PLACE,
// so assign COPIES of psi_cc and keep psi_cc itself raw.
//
// Tensor depth deepens once more: innerProduct(CoarseCoarseSiteObj,...) returns
// iScalar<vTTComplex>, so CComplex for the L2→L3 level is iScalar<iScalar<vTComplex>>.
//////////////////////////////////////////////////////////////////////
typedef typename CoarseCoarseVector::vector_object CoarseCoarseSiteObj;
typedef iScalar<vTTComplex> vTTTComplex;
typedef GeneralCoarsenedMatrix<CoarseCoarseSiteObj,vTTTComplex,NB> LittleDiracOperatorL3;
typedef typename LittleDiracOperatorL3::CoarseVector CoarseCoarseCoarseVector;
typedef Aggregation<CoarseCoarseSiteObj,vTTTComplex,NB> SubspaceL3;
typedef MGPreconditioner<CoarseCoarseSiteObj,vTTTComplex,NB> L2to3MG;
SubspaceL3 AggregatesL3(CoarseCoarseCoarse5d, CoarseCoarse5d, cb);
for (int k = 0; k < nbasis; k++)
AggregatesL3.subspace[k] = psi_cc[k]; // raw promoted; COPY, keeps psi_cc raw
NextToNearestStencilGeometry5D geom3(CoarseCoarseCoarse5d);
LittleDiracOperatorL3 LittleDiracOpL3(geom3, CoarseCoarse5d, CoarseCoarseCoarse5d);
LittleDiracOpL3.CoarsenOperator(LinOpCC, AggregatesL3); // block-GS's AggregatesL3.subspace in place
NonHermitianLinearOperator<LittleDiracOperatorL3,CoarseCoarseCoarseVector> LinOpCCC(LittleDiracOpL3);
TrivialPrecon<CoarseCoarseCoarseVector> simpleCCC;
//////////////////////////////////////////////////////////////////////
// Level 4 bottom solve: GCR on a SHIFTED LinOpCCC. This is the one level
// with no IRS shift, and it is the most non-normal (coarsest) operator, so
// the bare bottom GCR wanders in a field of values that wraps the origin and
// its iteration count blows out (observed 5..54 iters to hit 0.2). Solving
// (A_ccc + l4_shift) instead slides the FoV off the origin; the correction is
// only ever a loose 0.2 approximation anyway, so the detuning is free.
// l4_shift defaults to 0.0 => bare LinOpCCC, baseline unchanged until opted in.
//////////////////////////////////////////////////////////////////////
RealD l4_shift = 0.0;
if(getenv("l4_shift")) l4_shift = atof(getenv("l4_shift"));
std::cout << GridLogMessage << "PARAM l4_shift = " << l4_shift << std::endl;
ShiftedLinearOperator<CoarseCoarseCoarseVector> ShiftedLinOpCCC(l4_shift, LinOpCCC);
PrecGeneralisedConjugateResidualNonHermitian<CoarseCoarseCoarseVector> L4PGCR(1.0e-1,200,ShiftedLinOpCCC,simpleCCC,16,16);
L4PGCR.Level(4);
L4PGCR.Name("CCCouter");
//////////////////////////////////////////////////////////////////////
// Level 2→3 V-cycle: depth-2 SHIFTED smoother on LinOpCC + L4 bottom.
// The shift slides the coarse-coarse field of values off the origin so a
// 2-step smoother has something to bite on a non-normal operator (IRS idea).
//////////////////////////////////////////////////////////////////////
RealD cc_smoother_shift = 0.01;
int cc_smoother_nstep = 2;
if(getenv("cc_smoother_shift")) cc_smoother_shift = atof(getenv("cc_smoother_shift"));
if(getenv("cc_smoother_nstep")) cc_smoother_nstep = atoi(getenv("cc_smoother_nstep"));
ShiftedLinearOperator<CoarseCoarseVector> ShiftedLinOpCC(cc_smoother_shift, LinOpCC);
PrecGeneralisedConjugateResidualNonHermitian<CoarseCoarseVector>
CoarseCoarseSmootherGCR(0.01,1,ShiftedLinOpCC,simpleCC,cc_smoother_nstep,cc_smoother_nstep);
CoarseCoarseSmootherGCR.SetZeroGuess(1); // smoother slot: caller zeroes guess
CoarseCoarseSmootherGCR.Level(3);
CoarseCoarseSmootherGCR.Name("CCsmoother");
L2to3MG L2to3Precon(AggregatesL3,
LinOpCC,
simpleCC, // no pre-smoother
CoarseCoarseSmootherGCR, // post-smoother: depth-2 shifted GCR
LinOpCCC,
L4PGCR,
simpleCCC); // trivial guesser at the bottom
//////////////////////////////////////////////////////////////////////
// Level 3 (coarse-coarse) solve: GCR preconditioned by the L2→L3 V-cycle.
// Replaces the plain L3PGCR of the 3-level build -- the coarse-coarse level
// is now smoothed shallowly and recursed rather than solved deeply.
//////////////////////////////////////////////////////////////////////
PrecGeneralisedConjugateResidualNonHermitian<CoarseCoarseVector> L3MGsolver(1.0e-1,200,LinOpCC,L2to3Precon,16,16);
L3MGsolver.Level(3);
L3MGsolver.Name("CCouter");
//////////////////////////////////////////////////////////////////////
// Coarse-level GCR smoother for Level 1→2 V-cycle.
// Mirrors fine-grid SmootherGCR: shifted operator + fixed step count.
// coarse_smoother_shift and coarse_smoother_nstep are the tuning knobs.
//////////////////////////////////////////////////////////////////////
RealD coarse_smoother_shift = 0.01;
int coarse_smoother_nstep = 2; // depth-2 smoother on the coarse level
if(getenv("coarse_smoother_shift")) coarse_smoother_shift = atof(getenv("coarse_smoother_shift"));
if(getenv("coarse_smoother_nstep")) coarse_smoother_nstep = atoi(getenv("coarse_smoother_nstep"));
ShiftedLinearOperator<CoarseVector> ShiftedLinOpCoarse(coarse_smoother_shift, LinOpCoarse);
PrecGeneralisedConjugateResidualNonHermitian<CoarseVector> CoarseSmootherGCR(0.01,1,ShiftedLinOpCoarse,simpleC,coarse_smoother_nstep,coarse_smoother_nstep);
CoarseSmootherGCR.SetZeroGuess(1); // smoother slot: caller zeroes guess
CoarseSmootherGCR.Level(2);
CoarseSmootherGCR.Name("Csmoother");
//////////////////////////////////////////////////////////////////////
// Level 1→2 V-cycle preconditioner.
//////////////////////////////////////////////////////////////////////
L1to2MG L1to2Precon(AggregatesL2,
LinOpCoarse,
simpleC, // no pre-smoother (matches fine-grid setup)
CoarseSmootherGCR, // post-smoother: depth-2 shifted GCR
LinOpCC,
L3MGsolver, // coarse-coarse solve is now the L2→L3 V-cycle
CCDeflGuesser); // Lüscher guesser: psi_cc C^{-1} psi_cc†
//////////////////////////////////////////////////////////////////////
// Standalone Level 1 two-level solve test.
// Compare against plain PGCR baseline above.
//////////////////////////////////////////////////////////////////////
std::cout<<GridLogMessage<<"*******************************************"<<std::endl;
std::cout<<GridLogMessage<<" Level 1 solve: two-level MG preconditioned PGCR"<<std::endl;
std::cout<<GridLogMessage<<"*******************************************"<<std::endl;
PrecGeneralisedConjugateResidualNonHermitian<CoarseVector> L2MGsolver(3.0e-2,200,LinOpCoarse,L1to2Precon,16,16);
L2MGsolver.Level(2);
L2MGsolver.Name("Couter");
c_res = Zero();
L2MGsolver(c_src,c_res);
std::cout << GridLogMessage << "Level 1 two-level test: PVdagM operator uses:" << std::endl;
PVdagM.getApplications();
PVdagM.clear();
//////////////////////////////////////////////////////////////////////
// Full three-level outer solve
//////////////////////////////////////////////////////////////////////
std::cout<<GridLogMessage<<"*******************************************"<<std::endl;
std::cout<<GridLogMessage<<" Three-level outer solve"<<std::endl;
std::cout<<GridLogMessage<<"*******************************************"<<std::endl;
PrecGeneralisedConjugateResidualNonHermitian<LatticeFermionD> SmootherGCR(0.01,1,ShiftedPVdagM,simple_fine,16,16);
SmootherGCR.SetZeroGuess(1); // pre/post smoother slots zero their guess
SmootherGCR.Level(1);
SmootherGCR.Name("Fsmoother");
f_src = one;
// Pre-smoother: none (TrivialPrecon); post-smoother: shifted PGCR.
// Coarse solver: L2MGsolver (PGCR preconditioned by Level 1→2 V-cycle).
TwoLevelMG ThreeLevelPrecon(AggregatesPD,
PVdagM,
simple_fine,
SmootherGCR,
LinOpCoarse,
L2MGsolver,
simpleC);
PrecGeneralisedConjugateResidualNonHermitian<LatticeFermion> L1PGCR(1.0e-8,1000,PVdagM,ThreeLevelPrecon,16,16);
L1PGCR.Level(1);
L1PGCR.Name("Fouter");
f_res = Zero();
L1PGCR(f_src,f_res);
std::cout << GridLogMessage << "Three-level outer solve: PVdagM operator uses:" << std::endl;
PVdagM.getApplications();
PVdagM.clear();
}
int main (int argc, char ** argv)
{
Grid_init(&argc,&argv);
const int Ls = 24;
RealD M5 = 1.8;
RealD b = 1.5;
RealD c = 0.5;
RealD mass = 0.00078;
if ( getenv("MASS") ) mass = atof(getenv("MASS"));
const int nbasis = 60;
std::cout << GridLogMessage << "Mass: " << mass << ", Ls: " << Ls << ", b=" << b << ", c=" << c << std::endl;
std::cout << GridLogMessage << "nbasis: " << nbasis << std::endl;
std::vector<int> lat_size {48, 48, 48, 96};
GridCartesian * UGrid = SpaceTimeGrid::makeFourDimGrid(lat_size, GridDefaultSimd(Nd,vComplex::Nsimd()),GridDefaultMpi());
GridRedBlackCartesian * UrbGrid = SpaceTimeGrid::makeFourDimRedBlackGrid(UGrid);
GridCartesian * FGrid = SpaceTimeGrid::makeFiveDimGrid(Ls,UGrid);
GridRedBlackCartesian * FrbGrid = SpaceTimeGrid::makeFiveDimRedBlackGrid(Ls,UGrid);
// Level 1 coarse grid: block 2^4 from fine (48×48×48×96 → 24×24×24×48, Ls=1)
Coordinate clatt = lat_size;
for (int d = 0; d < 4; d++) clatt[d] /= 2;
std::cout << GridLogMessage << "Level 1 coarse lattice: " << clatt << std::endl;
GridCartesian *Coarse4d = SpaceTimeGrid::makeFourDimGrid(clatt, GridDefaultSimd(Nd,vComplex::Nsimd()),GridDefaultMpi());
GridCartesian *Coarse5d = SpaceTimeGrid::makeFiveDimGrid(1,Coarse4d);
// Level 2 coarse-coarse grid: block 2,2,3,3 from Level 1 (24×24×24×48 → 12×12×8×16, Ls=1).
// MPI geometry 3.6.4.4 (288 ranks): fine local {16,8,12,24}.
// Level 1 local {8,4,6,12}; Level 2 local {4,2,2,4}.
// z blocked by 3: z-Level1-local=6; 6/3=2 (even), 6/2=3 (odd) → must use 3.
// t blocked by 3: t-Level1-local=12; 12/3=4 divisible by Nsimd=4 (gen-simd-width=64).
// t-block=2 gives t2-local=6, 6 mod 4 ≠ 0, fails Grid SIMD assertion. ✓
// With {4,2,2,4}: Nsimd=4 goes into x or t (both =4). ✓
Coordinate clatt2 = clatt;
clatt2[0] /= 2;
clatt2[1] /= 2;
clatt2[2] /= 3;
clatt2[3] /= 3;
std::cout << GridLogMessage << "Level 2 coarse-coarse lattice: " << clatt2 << std::endl;
GridCartesian *CoarseCoarse4d = SpaceTimeGrid::makeFourDimGrid(clatt2, GridDefaultSimd(Nd,vComplex::Nsimd()),GridDefaultMpi());
GridCartesian *CoarseCoarse5d = SpaceTimeGrid::makeFiveDimGrid(1,CoarseCoarse4d);
// Level 3 coarse-coarse-coarse grid: block clatt2 = {12,12,8,16} -> {6,12,8,8}.
// GEOMETRY (mpi 3.6.4.4, Nsimd=4 => SIMD layout {1,1,2,2}, factor 2 on z and t):
// every grid needs z-local and t-local EVEN. clatt2-local is {4,2,2,4}, so
// z-local=2 is already at its minimum even value and CANNOT be blocked (2->1
// is odd and trips the SIMD assertion); y-local=2 would go to 1 (degenerate).
// Only x and t have room, so block {2,1,1,2}: clatt3 {6,12,8,8}, L4-local
// {2,2,2,2} -- all dims even and >=2. z stays unblocked by construction.
Coordinate clatt3 = clatt2;
clatt3[0] /= 2; // x: 12 -> 6 (x-local 4 -> 2)
// clatt3[1] (y) unblocked: y-local 2 -> blocking gives 1 (degenerate)
// clatt3[2] (z) unblocked: z-local 2 is SIMD-pinned even, cannot halve
clatt3[3] /= 2; // t: 16 -> 8 (t-local 4 -> 2)
std::cout << GridLogMessage << "Level 3 coarse-coarse-coarse lattice: " << clatt3 << std::endl;
GridCartesian *CoarseCoarseCoarse4d = SpaceTimeGrid::makeFourDimGrid(clatt3, GridDefaultSimd(Nd,vComplex::Nsimd()),GridDefaultMpi());
GridCartesian *CoarseCoarseCoarse5d = SpaceTimeGrid::makeFiveDimGrid(1,CoarseCoarseCoarse4d);
std::vector<int> seeds4({1,2,3,4});
std::vector<int> seeds5({5,6,7,8});
GridParallelRNG RNG5(FGrid); RNG5.SeedFixedIntegers(seeds5);
GridParallelRNG RNG4(UGrid); RNG4.SeedFixedIntegers(seeds4);
LatticeGaugeField Umu(UGrid);
std::cout << GridLogMessage << "Reading gauge field" << std::endl;
FieldMetaData header;
std::string file("/ccs/home/poare/ckpoint_lat.1000");
NerscIO::readConfiguration(Umu,header,file);
RealD b_ = 1.5;
RealD c_ = 0.5;
MobiusFermionD Ddwf(Umu,*FGrid,*FrbGrid,*UGrid,*UrbGrid,mass,M5,b_,c_);
MobiusFermionD Dpv (Umu,*FGrid,*FrbGrid,*UGrid,*UrbGrid,1.0, M5,b_,c_);
typedef PVdagMLinearOperator<MobiusFermionD,LatticeFermionD> PVdagM_t;
typedef ShiftedPVdagMLinearOperator<MobiusFermionD,LatticeFermionD> ShiftedPVdagM_t;
typedef GeneralCoarsenedMatrix<vSpinColourVector,vTComplex,nbasis> LittleDiracOperator;
typedef LittleDiracOperator::CoarseVector CoarseVector;
typedef Aggregation<vSpinColourVector,vTComplex,nbasis> Subspace;
typedef MGPreconditioner<vSpinColourVector,vTComplex,nbasis> TwoLevelMG;
PVdagM_t PVdagM(Ddwf,Dpv);
ShiftedPVdagM_t ShiftedPVdagM(0.01,Ddwf,Dpv);
NextToNearestStencilGeometry5D geom(Coarse5d);
// Subspace cache: save after generation, reload on subsequent runs to skip expensive setup.
// Set SUBSPACE_FILE to override the default path.
std::string subspace_file = "/lustre/orion/phy157/proj-shared/phy157_dwf/paboyle/subspace_nb"
+ std::to_string(nbasis) + ".scidac";
if ( getenv("SUBSPACE_FILE") ) subspace_file = std::string(getenv("SUBSPACE_FILE"));
// Check if subspace file exists (boss rank checks, result broadcast via GlobalSum).
uint64_t file_exists = 0;
if ( UGrid->IsBoss() ) {
std::ifstream f(subspace_file);
file_exists = f.good() ? 1 : 0;
}
UGrid->GlobalSum(file_exists);
const int cb = 0;
Subspace AggregatesGCR(Coarse5d,FGrid,cb);
if ( file_exists ) {
std::cout << GridLogMessage << "*** Loading subspace from disk ***" << std::endl;
loadSubspace(AggregatesGCR.subspace, subspace_file);
// Insurance: GLOBAL (whole-lattice) orthonormalise, in case the cached file
// predates the GlobalOrthonormalise() that CreateSubspaceGCR now applies
// (Aggregates.h:196). It is span-preserving and makes the vectors globally
// orthonormal -- it is NOT the block Orthogonalise() below, so it does NOT
// cause the psi_coarse->e_k trap. The RAW subspace copy in runMG happens
// AFTER this call, so the raw-null (pre-block-GS) discipline is preserved.
AggregatesGCR.GlobalOrthonormalise();
// DO NOT block-orthogonalise here: runMG copies subspace[] as the RAW
// (pre-block-GS) basis and CoarsenOperator block-GS's it in place later.
// Orthogonalising now defeats the raw-null discipline (psi_coarse -> e_k)
// and poisons L2/L3/L4. See project_block_orthogonalise_leak.
// AggregatesGCR.Orthogonalise();
std::cout << GridLogMessage << "Subspace loaded, globally orthonormalised (raw block basis preserved)." << std::endl;
} else {
std::cout << GridLogMessage << "*** GCR subspace generation ***" << std::endl;
AggregatesGCR.CreateSubspaceGCR(RNG5,PVdagM,nbasis);
std::cout << GridLogMessage << "Subspace generation: PVdagM operator uses:" << std::endl;
PVdagM.getApplications();
PVdagM.clear();
saveSubspace(AggregatesGCR.subspace, subspace_file);
std::cout << GridLogMessage << "Subspace saved to: " << subspace_file << std::endl;
}
runMG<nbasis,PVdagM_t,ShiftedPVdagM_t,Subspace,LittleDiracOperator,CoarseVector,TwoLevelMG>(
FGrid,
Coarse5d,
CoarseCoarse5d,
CoarseCoarseCoarse5d,
geom,
PVdagM,
ShiftedPVdagM,
AggregatesGCR
);
std::cout << GridLogMessage << "Done" << std::endl;
Grid_finalize();
return 0;
}