/[MITgcm]/MITgcm/pkg/seaice/seaice_jfnk.F
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revision 1.9 by mlosch, Mon Nov 12 09:46:38 2012 UTC revision 1.16 by mlosch, Thu Jan 17 08:51:15 2013 UTC
# Line 3  C $Name$ Line 3  C $Name$
3    
4  #include "SEAICE_OPTIONS.h"  #include "SEAICE_OPTIONS.h"
5    
6    C--  File seaice_jfnk.F: seaice jfnk dynamical solver S/R:
7    C--   Contents
8    C--   o SEAICE_JFNK
9    C--   o SEAICE_JFNK_UPDATE
10    
11  CBOP  CBOP
12  C     !ROUTINE: SEAICE_JFNK  C     !ROUTINE: SEAICE_JFNK
13  C     !INTERFACE:  C     !INTERFACE:
# Line 10  C     !INTERFACE: Line 15  C     !INTERFACE:
15    
16  C     !DESCRIPTION: \bv  C     !DESCRIPTION: \bv
17  C     *==========================================================*  C     *==========================================================*
18  C     | SUBROUTINE SEAICE_JFKF  C     | SUBROUTINE SEAICE_JFNK
19  C     | o Ice dynamics using a Jacobian-free Newton-Krylov solver  C     | o Ice dynamics using a Jacobian-free Newton-Krylov solver
20  C     |   following J.-F. Lemieux et al. Improving the numerical  C     |   following J.-F. Lemieux et al. Improving the numerical
21  C     |   convergence of viscous-plastic sea ice models with the  C     |   convergence of viscous-plastic sea ice models with the
# Line 55  C     !FUNCTIONS: Line 60  C     !FUNCTIONS:
60        LOGICAL  DIFFERENT_MULTIPLE        LOGICAL  DIFFERENT_MULTIPLE
61        EXTERNAL DIFFERENT_MULTIPLE        EXTERNAL DIFFERENT_MULTIPLE
62    
63    C     !LOCAL VARIABLES:
64    C     === Local variables ===
65  C     i,j,bi,bj :: loop indices  C     i,j,bi,bj :: loop indices
66        INTEGER i,j,bi,bj        INTEGER i,j,bi,bj
67  C     loop indices  C     loop indices
68        INTEGER newtonIter        INTEGER newtonIter
69        INTEGER krylovIter, krylovFails        INTEGER krylovIter, krylovFails
70        INTEGER totalKrylovItersLoc        INTEGER totalKrylovItersLoc, totalNewtonItersLoc
71  C     FGMRES flag that determines amount of output messages of fgmres  C     FGMRES flag that determines amount of output messages of fgmres
72        INTEGER iOutFGMRES        INTEGER iOutFGMRES
73  C     FGMRES flag that indicates what fgmres wants us to do next  C     FGMRES flag that indicates what fgmres wants us to do next
74        INTEGER iCode        INTEGER iCode
75        _RL     JFNKresidual, JFNKresidualTile(nSx,nSy)        _RL     JFNKresidual
76        _RL     JFNKresidualKm1        _RL     JFNKresidualKm1
77  C     parameters to compute convergence criterion  C     parameters to compute convergence criterion
78        _RL     phi_e, alp_e, JFNKgamma_lin        _RL     phi_e, alp_e, JFNKgamma_lin
# Line 80  C Line 87  C
87  C     u/vIceRes :: residual of sea-ice momentum equations  C     u/vIceRes :: residual of sea-ice momentum equations
88        _RL uIceRes(1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)        _RL uIceRes(1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)
89        _RL vIceRes(1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)        _RL vIceRes(1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)
90    C     vector version of the residuals
91          _RL resTmp (nVec,1,nSx,nSy)
92  C     du/vIce   :: ice velocity increment to be added to u/vIce  C     du/vIce   :: ice velocity increment to be added to u/vIce
93        _RL duIce  (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)        _RL duIce  (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)
94        _RL dvIce  (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)        _RL dvIce  (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)
# Line 89  C     zeta, eta, and DWATN, press Line 98  C     zeta, eta, and DWATN, press
98        _RL etaPre  (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)        _RL etaPre  (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)
99        _RL etaZPre (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)        _RL etaZPre (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)
100        _RL dwatPre (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)        _RL dwatPre (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)
       _RL pressPre(1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)  
101  CEOP  CEOP
102    
103  C     Initialise  C     Initialise
# Line 104  C     Initialise Line 112  C     Initialise
112        recip_deltaT        = 1. _d 0 / SEAICE_deltaTdyn        recip_deltaT        = 1. _d 0 / SEAICE_deltaTdyn
113    
114        iOutFGMRES=0        iOutFGMRES=0
115  C     iOutFgmres=1 gives a little bit of output  C     with iOutFgmres=1, seaice_fgmres prints the residual at each iteration
116        IF ( debugLevel.GE.debLevA .AND.        IF ( debugLevel.GE.debLevC .AND.
117       &     DIFFERENT_MULTIPLE( SEAICE_monFreq, myTime, deltaTClock ) )       &     DIFFERENT_MULTIPLE( SEAICE_monFreq, myTime, deltaTClock ) )
118       &     iOutFGMRES=1       &     iOutFGMRES=1
119    
# Line 141  C     Start nonlinear Newton iteration: Line 149  C     Start nonlinear Newton iteration:
149         newtonIter = newtonIter + 1         newtonIter = newtonIter + 1
150  C     Compute initial residual F(u), (includes computation of global  C     Compute initial residual F(u), (includes computation of global
151  C     variables DWATN, zeta, and eta)  C     variables DWATN, zeta, and eta)
152         CALL SEAICE_CALC_RESIDUAL(         IF ( newtonIter .EQ. 1 ) CALL SEAICE_JFNK_UPDATE(
153       I      uIce, vIce,       I      duIce, dvIce,
154       O      uIceRes, vIceRes,       U      uIce, vIce, JFNKresidual,
155       I      newtonIter, 0, myTime, myIter, myThid )       O      uIceRes, vIceRes,
156         CALL EXCH_UV_XY_RL( uIceRes, vIceRes,.TRUE.,myThid)       I      newtonIter, myTime, myIter, myThid )
157  C     local copies of precomputed coefficients that are to stay  C     local copies of precomputed coefficients that are to stay
158  C     constant for the preconditioner  C     constant for the preconditioner
159         DO bj=myByLo(myThid),myByHi(myThid)         DO bj=myByLo(myThid),myByHi(myThid)
160          DO bi=myBxLo(myThid),myBxHi(myThid)          DO bi=myBxLo(myThid),myBxHi(myThid)
161           DO j=1-Oly,sNy+Oly           DO j=1-Oly,sNy+Oly
162            DO i=1-Olx,sNx+Olx            DO i=1-Olx,sNx+Olx
163              zetaPre(I,J,bi,bj) =  zeta(I,J,bi,bj)             zetaPre(I,J,bi,bj) =  zeta(I,J,bi,bj)
164               etaPre(I,J,bi,bj) =   eta(I,J,bi,bj)              etaPre(I,J,bi,bj) =   eta(I,J,bi,bj)
165              etaZPre(I,J,bi,bj) =  etaZ(I,J,bi,bj)             etaZPre(I,J,bi,bj) =  etaZ(I,J,bi,bj)
166              dwatPre(I,J,bi,bj) = DWATN(I,J,bi,bj)             dwatPre(I,J,bi,bj) = DWATN(I,J,bi,bj)
            pressPre(I,J,bi,bj) = press(I,J,bi,bj)  
           ENDDO  
          ENDDO  
         ENDDO  
        ENDDO  
 C      
        DO bj=myByLo(myThid),myByHi(myThid)  
         DO bi=myBxLo(myThid),myBxHi(myThid)  
          JFNKresidualTile(bi,bj) = 0. _d 0  
          DO J=1,sNy  
           DO I=1,sNx  
 #ifdef CG2D_SINGLECPU_SUM  
            JFNKlocalBuf(I,J,bi,bj) =  
 #else  
            JFNKresidualTile(bi,bj) = JFNKresidualTile(bi,bj) +  
 #endif  
      &          uIceRes(I,J,bi,bj)*uIceRes(I,J,bi,bj) +  
      &          vIceRes(I,J,bi,bj)*vIceRes(I,J,bi,bj)  
167            ENDDO            ENDDO
168           ENDDO           ENDDO
169          ENDDO          ENDDO
170         ENDDO         ENDDO
        JFNKresidual = 0. _d 0  
 #ifdef CG2D_SINGLECPU_SUM  
        CALL GLOBAL_SUM_SINGLECPU_RL(  
      &         JFNKlocalBuf,JFNKresidual, 0, 0, myThid)  
 #else  
        CALL GLOBAL_SUM_TILE_RL( JFNKresidualTile,JFNKresidual,myThid )  
 #endif  
        JFNKresidual = SQRT(JFNKresidual)  
171  C     compute convergence criterion for linear preconditioned FGMRES  C     compute convergence criterion for linear preconditioned FGMRES
172         JFNKgamma_lin = JFNKgamma_lin_max         JFNKgamma_lin = JFNKgamma_lin_max
173         IF ( newtonIter.GT.1.AND.newtonIter.LE.100         IF ( newtonIter.GT.1.AND.newtonIter.LE.100
# Line 207  C     krylovIter is mapped into "its" in Line 189  C     krylovIter is mapped into "its" in
189  C     in that routine  C     in that routine
190         krylovIter    = 0         krylovIter    = 0
191         iCode         = 0         iCode         = 0
        IF ( debugLevel.GE.debLevA ) THEN    
         _BEGIN_MASTER( myThid )  
         WRITE(msgBuf,'(2A,2(1XI6),2E12.5)')  
      &       ' S/R SEAICE_JFNK: newtonIter,',  
      &       ' total newtonIter, JFNKgamma_lin, initial norm = ',  
      &       newtonIter,SEAICEnewtonIterMax*(myIter-nIter0)+newtonIter,  
      &       JFNKgamma_lin, JFNKresidual  
         CALL PRINT_MESSAGE( msgBuf, standardMessageUnit,  
      &       SQUEEZE_RIGHT, myThid )  
         _END_MASTER( myThid )  
        ENDIF  
192  C  C
193         JFNKconverged = JFNKresidual.LT.JFNKtol         JFNKconverged = JFNKresidual.LT.JFNKtol
194  C  C
# Line 247  C     Call preconditioner Line 218  C     Call preconditioner
218            IF ( SOLV_MAX_ITERS .GT. 0 )            IF ( SOLV_MAX_ITERS .GT. 0 )
219       &         CALL SEAICE_PRECONDITIONER(       &         CALL SEAICE_PRECONDITIONER(
220       U         duIce, dvIce,       U         duIce, dvIce,
221       I         zetaPre, etaPre, etaZpre, dwatPre, pressPre,       I         zetaPre, etaPre, etaZpre, dwatPre,
222       I         newtonIter, krylovIter, myTime, myIter, myThid )       I         newtonIter, krylovIter, myTime, myIter, myThid )
223           ELSEIF (iCode.GE.2) THEN           ELSEIF (iCode.GE.2) THEN
224  C     Compute Jacobian times vector  C     Compute Jacobian times vector
# Line 263  C     End of Krylov iterate Line 234  C     End of Krylov iterate
234  C     some output diagnostics  C     some output diagnostics
235          IF ( debugLevel.GE.debLevA ) THEN          IF ( debugLevel.GE.debLevA ) THEN
236           _BEGIN_MASTER( myThid )           _BEGIN_MASTER( myThid )
237             totalNewtonItersLoc =
238         &        SEAICEnewtonIterMax*(myIter-nIter0)+newtonIter
239             WRITE(msgBuf,'(2A,2(1XI6),2E12.5)')
240         &        ' S/R SEAICE_JFNK: Newton iterate / total, ',
241         &        'JFNKgamma_lin, initial norm = ',
242         &        newtonIter, totalNewtonItersLoc,
243         &        JFNKgamma_lin,JFNKresidual
244             CALL PRINT_MESSAGE( msgBuf, standardMessageUnit,
245         &        SQUEEZE_RIGHT, myThid )
246           WRITE(msgBuf,'(3(A,I6))')           WRITE(msgBuf,'(3(A,I6))')
247       &        ' S/R SEAICE_JFNK: Newton iterate / total = ', newtonIter,       &        ' S/R SEAICE_JFNK: Newton iterate / total = ',newtonIter,
248       &        ' / ', SEAICEnewtonIterMax*(myIter-nIter0)+newtonIter,       &        ' / ', totalNewtonItersLoc,
249       &        ', Nb. of FGMRES iterations = ', krylovIter       &        ', Nb. of FGMRES iterations = ', krylovIter
250           CALL PRINT_MESSAGE( msgBuf, standardMessageUnit,           CALL PRINT_MESSAGE( msgBuf, standardMessageUnit,
251       &        SQUEEZE_RIGHT, myThid )       &        SQUEEZE_RIGHT, myThid )
# Line 274  C     some output diagnostics Line 254  C     some output diagnostics
254          IF ( krylovIter.EQ.SEAICEkrylovIterMax ) THEN          IF ( krylovIter.EQ.SEAICEkrylovIterMax ) THEN
255           krylovFails = krylovFails + 1           krylovFails = krylovFails + 1
256          ENDIF          ENDIF
257    C     Set the stopping criterion for the Newton iteration
258            IF ( newtonIter .EQ. 1 ) JFNKtol=JFNKgamma_nonlin*JFNKresidual
259  C     Update linear solution vector and return to Newton iteration  C     Update linear solution vector and return to Newton iteration
260    C     Do a linesearch if necessary, and compute a new residual.
261    C     Note that it should be possible to do the following operations
262    C     at the beginning of the Newton iteration, thereby saving us from
263    C     the extra call of seaice_jfnk_update, but unfortunately that
264    C     changes the results, so we leave the stuff here for now.
265            CALL SEAICE_JFNK_UPDATE(
266         I       duIce, dvIce,
267         U       uIce, vIce, JFNKresidual,
268         O       uIceRes, vIceRes,
269         I       newtonIter, myTime, myIter, myThid )
270    C     reset du/vIce here instead of setting sol = 0 in seaice_fgmres_driver
271          DO bj=myByLo(myThid),myByHi(myThid)          DO bj=myByLo(myThid),myByHi(myThid)
272           DO bi=myBxLo(myThid),myBxHi(myThid)           DO bi=myBxLo(myThid),myBxHi(myThid)
273            DO J=1-Oly,sNy+Oly            DO J=1-Oly,sNy+Oly
274             DO I=1-Olx,sNx+Olx             DO I=1-Olx,sNx+Olx
             uIce(I,J,bi,bj) = uIce(I,J,bi,bj)+duIce(I,J,bi,bj)  
             vIce(I,J,bi,bj) = vIce(I,J,bi,bj)+dvIce(I,J,bi,bj)  
 C     reset du/vIce here instead of setting sol = 0 in seaice_fgmres_driver  
275              duIce(I,J,bi,bj)= 0. _d 0              duIce(I,J,bi,bj)= 0. _d 0
276              dvIce(I,J,bi,bj)= 0. _d 0              dvIce(I,J,bi,bj)= 0. _d 0
277             ENDDO             ENDDO
278            ENDDO            ENDDO
279           ENDDO           ENDDO
280          ENDDO          ENDDO
 C     Set the stopping criterion for the Newton iteration  
         IF ( newtonIter .EQ. 1 ) JFNKtol=JFNKgamma_nonlin*JFNKresidual  
281         ENDIF         ENDIF
282  C     end of Newton iterate  C     end of Newton iterate
283        ENDDO        ENDDO
# Line 359  C     Decide whether it is time to dump Line 347  C     Decide whether it is time to dump
347       &' // ======================================================='       &' // ======================================================='
348         CALL PRINT_MESSAGE( msgBuf, standardMessageUnit,         CALL PRINT_MESSAGE( msgBuf, standardMessageUnit,
349       &      SQUEEZE_RIGHT, myThid )       &      SQUEEZE_RIGHT, myThid )
350         WRITE(msgBuf,'(A)') ' // Begin JFNK statistics'         WRITE(msgBuf,'(A)') ' // End JFNK statistics'
351         CALL PRINT_MESSAGE( msgBuf, standardMessageUnit,         CALL PRINT_MESSAGE( msgBuf, standardMessageUnit,
352       &      SQUEEZE_RIGHT, myThid )       &      SQUEEZE_RIGHT, myThid )
353         WRITE(msgBuf,'(A)')         WRITE(msgBuf,'(A)')
# Line 404  C     Print more debugging information Line 392  C     Print more debugging information
392         _END_MASTER( myThid )         _END_MASTER( myThid )
393        ENDIF        ENDIF
394    
395          RETURN
396          END
397    
398    C---+----1----+----2----+----3----+----4----+----5----+----6----+----7-|--+----|
399    CBOP
400    C     !ROUTINE: SEAICE_JFNK_UPDATE
401    C     !INTERFACE:
402    
403          SUBROUTINE SEAICE_JFNK_UPDATE(
404         I     duIce, dvIce,
405         U     uIce, vIce, JFNKresidual,
406         O     uIceRes, vIceRes,
407         I     newtonIter, myTime, myIter, myThid )
408    
409    C     !DESCRIPTION: \bv
410    C     *==========================================================*
411    C     | SUBROUTINE SEAICE_JFNK_UPDATE
412    C     | o Update velocities with incremental solutions of FGMRES
413    C     | o compute residual of updated solutions and do
414    C     | o linesearch:
415    C     |   reduce update until residual is smaller than previous
416    C     |   one (input)
417    C     *==========================================================*
418    C     | written by Martin Losch, Jan 2013
419    C     *==========================================================*
420    C     \ev
421    
422    C     !USES:
423          IMPLICIT NONE
424    
425    C     === Global variables ===
426    #include "SIZE.h"
427    #include "EEPARAMS.h"
428    #include "PARAMS.h"
429    #include "SEAICE_SIZE.h"
430    #include "SEAICE_PARAMS.h"
431    
432    C     !INPUT/OUTPUT PARAMETERS:
433    C     === Routine arguments ===
434    C     myTime :: Simulation time
435    C     myIter :: Simulation timestep number
436    C     myThid :: my Thread Id. number
437    C     newtonIter :: current iterate of Newton iteration
438          _RL     myTime
439          INTEGER myIter
440          INTEGER myThid
441          INTEGER newtonIter
442    C     JFNKresidual :: Residual at the beginning of the FGMRES iteration,
443    C                     changes with newtonIter (updated)
444          _RL     JFNKresidual
445    C     du/vIce   :: ice velocity increment to be added to u/vIce (input)
446          _RL duIce  (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)
447          _RL dvIce  (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)
448    C     u/vIce    :: ice velocity increment to be added to u/vIce (updated)
449          _RL uIce   (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)
450          _RL vIce   (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)
451    C     u/vIceRes :: residual of sea-ice momentum equations (output)
452          _RL uIceRes(1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)
453          _RL vIceRes(1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)
454    
455    C     !LOCAL VARIABLES:
456    C     === Local variables ===
457    C     i,j,bi,bj :: loop indices
458          INTEGER i,j,bi,bj
459          INTEGER l
460          _RL     resLoc, facLS
461          LOGICAL doLineSearch
462    C     nVec    :: size of the input vector(s)
463    C     vector version of the residuals
464          INTEGER nVec
465          PARAMETER ( nVec  = 2*sNx*sNy )
466          _RL resTmp (nVec,1,nSx,nSy)
467    C
468          CHARACTER*(MAX_LEN_MBUF) msgBuf
469    CEOP
470    
471    C     Initialise some local variables
472          l = 0
473          resLoc = JFNKresidual
474          facLS = 1. _d 0
475          doLineSearch = .TRUE.
476          DO WHILE ( doLineSearch )
477    C     Determine, if we need more iterations
478           doLineSearch = resLoc .GE. JFNKresidual
479    C     Limit the maximum number of iterations arbitrarily to four
480           doLineSearch = doLineSearch .AND. l .LE. 4
481    C     For the first iteration du/vIce = 0 and there will be no
482    C     improvement of the residual possible, so we do only the first
483    C     iteration
484           IF ( newtonIter .EQ. 1 ) doLineSearch = .FALSE.
485    C     Only start a linesearch after some Newton iterations
486           IF ( newtonIter .LE. SEAICE_JFNK_lsIter ) doLineSearch = .FALSE.
487    C     Increment counter
488           l = l + 1
489    C     Create update
490           DO bj=myByLo(myThid),myByHi(myThid)
491            DO bi=myBxLo(myThid),myBxHi(myThid)
492             DO J=1-Oly,sNy+Oly
493              DO I=1-Olx,sNx+Olx
494               uIce(I,J,bi,bj) = uIce(I,J,bi,bj)+facLS*duIce(I,J,bi,bj)
495               vIce(I,J,bi,bj) = vIce(I,J,bi,bj)+facLS*dvIce(I,J,bi,bj)
496              ENDDO
497             ENDDO
498            ENDDO
499           ENDDO
500    C     Compute current residual F(u), (includes re-computation of global
501    C     variables DWATN, zeta, and eta, i.e. they are different after this)
502           CALL SEAICE_CALC_RESIDUAL(
503         I      uIce, vIce,
504         O      uIceRes, vIceRes,
505         I      newtonIter, 0, myTime, myIter, myThid )
506    C     Important: Compute the norm of the residual using the same scalar
507    C     product that SEAICE_FGMRES does
508           CALL SEAICE_MAP2VEC(nVec,uIceRes,vIceRes,resTmp,.TRUE.,myThid)
509           CALL SEAICE_SCALPROD(nVec,1,1,1,resTmp,resTmp,resLoc,myThid)
510           resLoc = SQRT(resLoc)
511    C     some output diagnostics
512           IF ( debugLevel.GE.debLevA .AND. doLineSearch ) THEN
513            _BEGIN_MASTER( myThid )
514            WRITE(msgBuf,'(2A,2(1XI6),3E12.5)')
515         &       ' S/R SEAICE_JFNK_UPDATE: Newton iter, LSiter, ',
516         &       'facLS, JFNKresidual, resLoc = ',
517         &        newtonIter, l, facLS, JFNKresidual, resLoc
518            CALL PRINT_MESSAGE( msgBuf, standardMessageUnit,
519         &       SQUEEZE_RIGHT, myThid )
520            _END_MASTER( myThid )
521           ENDIF
522    C     Get ready for the next iteration: after adding du/vIce in the first
523    C     iteration, we substract 0.5*du/vIce from u/vIce in the next
524    C     iterations, 0.25*du/vIce in the second, etc.
525           facLS = - 0.5 _d 0 * ABS(facLS)
526          ENDDO
527    C     This is the new residual
528          JFNKresidual = resLoc
529    
530  #endif /* SEAICE_ALLOW_DYNAMICS and SEAICE_CGRID and SEAICE_ALLOW_JFNK */  #endif /* SEAICE_ALLOW_DYNAMICS and SEAICE_CGRID and SEAICE_ALLOW_JFNK */
531    
532        RETURN        RETURN
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