/[MITgcm]/MITgcm/pkg/seaice/seaice_jfnk.F
ViewVC logotype

Contents of /MITgcm/pkg/seaice/seaice_jfnk.F

Parent Directory Parent Directory | Revision Log Revision Log | View Revision Graph Revision Graph


Revision 1.12 - (show annotations) (download)
Mon Dec 17 10:08:16 2012 UTC (12 years, 7 months ago) by mlosch
Branch: MAIN
Changes since 1.11: +4 -3 lines
only print residuals at each krylov iteration for debugLevel.ge.debLevC

1 C $Header: /u/gcmpack/MITgcm/pkg/seaice/seaice_jfnk.F,v 1.11 2012/12/03 15:49:17 mlosch Exp $
2 C $Name: $
3
4 #include "SEAICE_OPTIONS.h"
5
6 CBOP
7 C !ROUTINE: SEAICE_JFNK
8 C !INTERFACE:
9 SUBROUTINE SEAICE_JFNK( myTime, myIter, myThid )
10
11 C !DESCRIPTION: \bv
12 C *==========================================================*
13 C | SUBROUTINE SEAICE_JFKF
14 C | o Ice dynamics using a Jacobian-free Newton-Krylov solver
15 C | following J.-F. Lemieux et al. Improving the numerical
16 C | convergence of viscous-plastic sea ice models with the
17 C | Jacobian-free Newton-Krylov method. J. Comp. Phys. 229,
18 C | 2840-2852 (2010).
19 C | o The logic follows JFs code.
20 C *==========================================================*
21 C | written by Martin Losch, Oct 2012
22 C *==========================================================*
23 C \ev
24
25 C !USES:
26 IMPLICIT NONE
27
28 C === Global variables ===
29 #include "SIZE.h"
30 #include "EEPARAMS.h"
31 #include "PARAMS.h"
32 #include "DYNVARS.h"
33 #include "GRID.h"
34 #include "SEAICE_SIZE.h"
35 #include "SEAICE_PARAMS.h"
36 #include "SEAICE.h"
37
38 #ifdef ALLOW_AUTODIFF_TAMC
39 # include "tamc.h"
40 #endif
41
42 C !INPUT/OUTPUT PARAMETERS:
43 C === Routine arguments ===
44 C myTime :: Simulation time
45 C myIter :: Simulation timestep number
46 C myThid :: my Thread Id. number
47 _RL myTime
48 INTEGER myIter
49 INTEGER myThid
50
51 #if ( (defined SEAICE_CGRID) && \
52 (defined SEAICE_ALLOW_JFNK) && \
53 (defined SEAICE_ALLOW_DYNAMICS) )
54 C !FUNCTIONS:
55 LOGICAL DIFFERENT_MULTIPLE
56 EXTERNAL DIFFERENT_MULTIPLE
57
58 C i,j,bi,bj :: loop indices
59 INTEGER i,j,bi,bj
60 C loop indices
61 INTEGER newtonIter
62 INTEGER krylovIter, krylovFails
63 INTEGER totalKrylovItersLoc
64 C FGMRES flag that determines amount of output messages of fgmres
65 INTEGER iOutFGMRES
66 C FGMRES flag that indicates what fgmres wants us to do next
67 INTEGER iCode
68 _RL JFNKresidual, JFNKresidualTile(nSx,nSy)
69 _RL JFNKresidualKm1
70 C parameters to compute convergence criterion
71 _RL phi_e, alp_e, JFNKgamma_lin
72 _RL FGMRESeps
73 _RL JFNKtol
74 C
75 _RL recip_deltaT
76 LOGICAL JFNKconverged, krylovConverged
77 LOGICAL writeNow
78 CHARACTER*(MAX_LEN_MBUF) msgBuf
79 C
80 C u/vIceRes :: residual of sea-ice momentum equations
81 _RL uIceRes(1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)
82 _RL vIceRes(1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)
83 C du/vIce :: ice velocity increment to be added to u/vIce
84 _RL duIce (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)
85 _RL dvIce (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)
86 C precomputed (= constant per Newton iteration) versions of
87 C zeta, eta, and DWATN, press
88 _RL zetaPre (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)
89 _RL etaPre (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)
90 _RL etaZPre (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)
91 _RL dwatPre (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)
92 CEOP
93
94 C Initialise
95 newtonIter = 0
96 krylovFails = 0
97 totalKrylovItersLoc = 0
98 JFNKconverged = .FALSE.
99 JFNKtol = 0. _d 0
100 JFNKresidual = 0. _d 0
101 JFNKresidualKm1 = 0. _d 0
102 FGMRESeps = 0. _d 0
103 recip_deltaT = 1. _d 0 / SEAICE_deltaTdyn
104
105 iOutFGMRES=0
106 C with iOutFgmres=1, seaice_fgmres prints the residual at each iteration
107 IF ( debugLevel.GE.debLevC .AND.
108 & DIFFERENT_MULTIPLE( SEAICE_monFreq, myTime, deltaTClock ) )
109 & iOutFGMRES=1
110
111 C
112 DO bj=myByLo(myThid),myByHi(myThid)
113 DO bi=myBxLo(myThid),myBxHi(myThid)
114 DO J=1-Oly,sNy+Oly
115 DO I=1-Olx,sNx+Olx
116 uIceRes(I,J,bi,bj) = 0. _d 0
117 vIceRes(I,J,bi,bj) = 0. _d 0
118 duIce (I,J,bi,bj) = 0. _d 0
119 dvIce (I,J,bi,bj) = 0. _d 0
120 uIceNm1(I,J,bi,bj) = uIce(I,J,bi,bj)
121 vIceNm1(I,J,bi,bj) = vIce(I,J,bi,bj)
122 ENDDO
123 ENDDO
124 C Compute things that do no change during the Newton iteration:
125 C sea-surface tilt and wind stress:
126 C FORCEX/Y0 - mass*(u/vIceNm1)/deltaT
127 DO J=1-Oly,sNy+Oly
128 DO I=1-Olx,sNx+Olx
129 FORCEX(I,J,bi,bj) = FORCEX0(I,J,bi,bj)
130 & + seaiceMassU(I,J,bi,bj)*uIceNm1(I,J,bi,bj)*recip_deltaT
131 FORCEY(I,J,bi,bj) = FORCEY0(I,J,bi,bj)
132 & + seaiceMassV(I,J,bi,bj)*vIceNm1(I,J,bi,bj)*recip_deltaT
133 ENDDO
134 ENDDO
135 ENDDO
136 ENDDO
137 C Start nonlinear Newton iteration: outer loop iteration
138 DO WHILE ( newtonIter.LT.SEAICEnewtonIterMax .AND.
139 & .NOT.JFNKconverged )
140 newtonIter = newtonIter + 1
141 C Compute initial residual F(u), (includes computation of global
142 C variables DWATN, zeta, and eta)
143 CALL SEAICE_CALC_RESIDUAL(
144 I uIce, vIce,
145 O uIceRes, vIceRes,
146 I newtonIter, 0, myTime, myIter, myThid )
147 C probably not necessary, will be removed later:
148 CALL EXCH_UV_XY_RL( uIceRes, vIceRes,.TRUE.,myThid)
149 C local copies of precomputed coefficients that are to stay
150 C constant for the preconditioner
151 DO bj=myByLo(myThid),myByHi(myThid)
152 DO bi=myBxLo(myThid),myBxHi(myThid)
153 DO j=1-Oly,sNy+Oly
154 DO i=1-Olx,sNx+Olx
155 zetaPre(I,J,bi,bj) = zeta(I,J,bi,bj)
156 etaPre(I,J,bi,bj) = eta(I,J,bi,bj)
157 etaZPre(I,J,bi,bj) = etaZ(I,J,bi,bj)
158 dwatPre(I,J,bi,bj) = DWATN(I,J,bi,bj)
159 ENDDO
160 ENDDO
161 ENDDO
162 ENDDO
163 C
164 DO bj=myByLo(myThid),myByHi(myThid)
165 DO bi=myBxLo(myThid),myBxHi(myThid)
166 JFNKresidualTile(bi,bj) = 0. _d 0
167 DO J=1,sNy
168 DO I=1,sNx
169 #ifdef CG2D_SINGLECPU_SUM
170 JFNKlocalBuf(I,J,bi,bj) =
171 #else
172 JFNKresidualTile(bi,bj) = JFNKresidualTile(bi,bj) +
173 #endif
174 & uIceRes(I,J,bi,bj)*uIceRes(I,J,bi,bj) +
175 & vIceRes(I,J,bi,bj)*vIceRes(I,J,bi,bj)
176 ENDDO
177 ENDDO
178 ENDDO
179 ENDDO
180 JFNKresidual = 0. _d 0
181 #ifdef CG2D_SINGLECPU_SUM
182 CALL GLOBAL_SUM_SINGLECPU_RL(
183 & JFNKlocalBuf,JFNKresidual, 0, 0, myThid)
184 #else
185 CALL GLOBAL_SUM_TILE_RL( JFNKresidualTile,JFNKresidual,myThid )
186 #endif
187 JFNKresidual = SQRT(JFNKresidual)
188 C compute convergence criterion for linear preconditioned FGMRES
189 JFNKgamma_lin = JFNKgamma_lin_max
190 IF ( newtonIter.GT.1.AND.newtonIter.LE.100
191 & .AND.JFNKresidual.LT.JFNKres_t ) THEN
192 C Eisenstat, 1996, equ.(2.6)
193 phi_e = 1. _d 0
194 alp_e = 1. _d 0
195 JFNKgamma_lin = phi_e*( JFNKresidual/JFNKresidualKm1 )**alp_e
196 JFNKgamma_lin = min(JFNKgamma_lin_max, JFNKgamma_lin)
197 JFNKgamma_lin = max(JFNKgamma_lin_min, JFNKgamma_lin)
198 ENDIF
199 C save the residual for the next iteration
200 JFNKresidualKm1 = JFNKresidual
201 C
202 C The Krylov iteration using FGMRES, the preconditioner is LSOR
203 C for now. The code is adapted from SEAICE_LSR, but heavily stripped
204 C down.
205 C krylovIter is mapped into "its" in seaice_fgmres and is incremented
206 C in that routine
207 krylovIter = 0
208 iCode = 0
209 IF ( debugLevel.GE.debLevA ) THEN
210 _BEGIN_MASTER( myThid )
211 WRITE(msgBuf,'(2A,2(1XI6),2E12.5)')
212 & ' S/R SEAICE_JFNK: newtonIter,',
213 & ' total newtonIter, JFNKgamma_lin, initial norm = ',
214 & newtonIter,SEAICEnewtonIterMax*(myIter-nIter0)+newtonIter,
215 & JFNKgamma_lin, JFNKresidual
216 CALL PRINT_MESSAGE( msgBuf, standardMessageUnit,
217 & SQUEEZE_RIGHT, myThid )
218 _END_MASTER( myThid )
219 ENDIF
220 C
221 JFNKconverged = JFNKresidual.LT.JFNKtol
222 C
223 C do Krylov loop only if convergence is not reached
224 C
225 IF ( .NOT.JFNKconverged ) THEN
226 C
227 C start Krylov iteration (FGMRES)
228 C
229 krylovConverged = .FALSE.
230 FGMRESeps = JFNKgamma_lin * JFNKresidual
231 DO WHILE ( .NOT.krylovConverged )
232 C solution vector sol = du/vIce
233 C residual vector (rhs) Fu = u/vIceRes
234 C output work vectors wk1, -> input work vector wk2
235 C
236 CALL SEAICE_FGMRES_DRIVER(
237 I uIceRes, vIceRes,
238 U duIce, dvIce, iCode,
239 I FGMRESeps, iOutFGMRES,
240 I newtonIter, krylovIter, myTime, myIter, myThid )
241 C FGMRES returns iCode either asking for an new preconditioned vector
242 C or product of matrix (Jacobian) times vector. For iCode = 0, terminate
243 C iteration
244 IF (iCode.EQ.1) THEN
245 C Call preconditioner
246 IF ( SOLV_MAX_ITERS .GT. 0 )
247 & CALL SEAICE_PRECONDITIONER(
248 U duIce, dvIce,
249 I zetaPre, etaPre, etaZpre, dwatPre,
250 I newtonIter, krylovIter, myTime, myIter, myThid )
251 ELSEIF (iCode.GE.2) THEN
252 C Compute Jacobian times vector
253 CALL SEAICE_JACVEC(
254 I uIce, vIce, uIceRes, vIceRes,
255 U duIce, dvIce,
256 I newtonIter, krylovIter, myTime, myIter, myThid )
257 ENDIF
258 krylovConverged = iCode.EQ.0
259 C End of Krylov iterate
260 ENDDO
261 totalKrylovItersLoc = totalKrylovItersLoc + krylovIter
262 C some output diagnostics
263 IF ( debugLevel.GE.debLevA ) THEN
264 _BEGIN_MASTER( myThid )
265 WRITE(msgBuf,'(3(A,I6))')
266 & ' S/R SEAICE_JFNK: Newton iterate / total = ', newtonIter,
267 & ' / ', SEAICEnewtonIterMax*(myIter-nIter0)+newtonIter,
268 & ', Nb. of FGMRES iterations = ', krylovIter
269 CALL PRINT_MESSAGE( msgBuf, standardMessageUnit,
270 & SQUEEZE_RIGHT, myThid )
271 _END_MASTER( myThid )
272 ENDIF
273 IF ( krylovIter.EQ.SEAICEkrylovIterMax ) THEN
274 krylovFails = krylovFails + 1
275 ENDIF
276 C Update linear solution vector and return to Newton iteration
277 DO bj=myByLo(myThid),myByHi(myThid)
278 DO bi=myBxLo(myThid),myBxHi(myThid)
279 DO J=1-Oly,sNy+Oly
280 DO I=1-Olx,sNx+Olx
281 uIce(I,J,bi,bj) = uIce(I,J,bi,bj)+duIce(I,J,bi,bj)
282 vIce(I,J,bi,bj) = vIce(I,J,bi,bj)+dvIce(I,J,bi,bj)
283 C reset du/vIce here instead of setting sol = 0 in seaice_fgmres_driver
284 duIce(I,J,bi,bj)= 0. _d 0
285 dvIce(I,J,bi,bj)= 0. _d 0
286 ENDDO
287 ENDDO
288 ENDDO
289 ENDDO
290 C Set the stopping criterion for the Newton iteration
291 IF ( newtonIter .EQ. 1 ) JFNKtol=JFNKgamma_nonlin*JFNKresidual
292 ENDIF
293 C end of Newton iterate
294 ENDDO
295 C
296 C-- Output diagnostics
297 C
298 IF ( SEAICE_monFreq .GT. 0. _d 0 ) THEN
299 C Count iterations
300 totalJFNKtimeSteps = totalJFNKtimeSteps + 1
301 totalNewtonIters = totalNewtonIters + newtonIter
302 totalKrylovIters = totalKrylovIters + totalKrylovItersLoc
303 C Record failure
304 totalKrylovFails = totalKrylovFails + krylovFails
305 IF ( newtonIter .EQ. SEAICEnewtonIterMax ) THEN
306 totalNewtonFails = totalNewtonFails + 1
307 ENDIF
308 ENDIF
309 C Decide whether it is time to dump and reset the counter
310 writeNow = DIFFERENT_MULTIPLE(SEAICE_monFreq,
311 & myTime+deltaTClock, deltaTClock)
312 #ifdef ALLOW_CAL
313 IF ( useCAL ) THEN
314 CALL CAL_TIME2DUMP(
315 I zeroRL, SEAICE_monFreq, deltaTClock,
316 U writeNow,
317 I myTime+deltaTclock, myIter+1, myThid )
318 ENDIF
319 #endif
320 IF ( writeNow ) THEN
321 _BEGIN_MASTER( myThid )
322 WRITE(msgBuf,'(A)')
323 &' // ======================================================='
324 CALL PRINT_MESSAGE( msgBuf, standardMessageUnit,
325 & SQUEEZE_RIGHT, myThid )
326 WRITE(msgBuf,'(A)') ' // Begin JFNK statistics'
327 CALL PRINT_MESSAGE( msgBuf, standardMessageUnit,
328 & SQUEEZE_RIGHT, myThid )
329 WRITE(msgBuf,'(A)')
330 &' // ======================================================='
331 CALL PRINT_MESSAGE( msgBuf, standardMessageUnit,
332 & SQUEEZE_RIGHT, myThid )
333 WRITE(msgBuf,'(A,I10)')
334 & ' %JFNK_MON: time step = ', myIter+1
335 CALL PRINT_MESSAGE( msgBuf, standardMessageUnit,
336 & SQUEEZE_RIGHT, myThid )
337 WRITE(msgBuf,'(A,I10)')
338 & ' %JFNK_MON: Nb. of time steps = ', totalJFNKtimeSteps
339 CALL PRINT_MESSAGE( msgBuf, standardMessageUnit,
340 & SQUEEZE_RIGHT, myThid )
341 WRITE(msgBuf,'(A,I10)')
342 & ' %JFNK_MON: Nb. of Newton steps = ', totalNewtonIters
343 CALL PRINT_MESSAGE( msgBuf, standardMessageUnit,
344 & SQUEEZE_RIGHT, myThid )
345 WRITE(msgBuf,'(A,I10)')
346 & ' %JFNK_MON: Nb. of Krylov steps = ', totalKrylovIters
347 CALL PRINT_MESSAGE( msgBuf, standardMessageUnit,
348 & SQUEEZE_RIGHT, myThid )
349 WRITE(msgBuf,'(A,I10)')
350 & ' %JFNK_MON: Nb. of Newton failures = ', totalNewtonFails
351 CALL PRINT_MESSAGE( msgBuf, standardMessageUnit,
352 & SQUEEZE_RIGHT, myThid )
353 WRITE(msgBuf,'(A,I10)')
354 & ' %JFNK_MON: Nb. of Krylov failures = ', totalKrylovFails
355 CALL PRINT_MESSAGE( msgBuf, standardMessageUnit,
356 & SQUEEZE_RIGHT, myThid )
357 WRITE(msgBuf,'(A)')
358 &' // ======================================================='
359 CALL PRINT_MESSAGE( msgBuf, standardMessageUnit,
360 & SQUEEZE_RIGHT, myThid )
361 WRITE(msgBuf,'(A)') ' // End JFNK statistics'
362 CALL PRINT_MESSAGE( msgBuf, standardMessageUnit,
363 & SQUEEZE_RIGHT, myThid )
364 WRITE(msgBuf,'(A)')
365 &' // ======================================================='
366 CALL PRINT_MESSAGE( msgBuf, standardMessageUnit,
367 & SQUEEZE_RIGHT, myThid )
368 _END_MASTER( myThid )
369 C reset and start again
370 totalJFNKtimeSteps = 0
371 totalNewtonIters = 0
372 totalKrylovIters = 0
373 totalKrylovFails = 0
374 totalNewtonFails = 0
375 ENDIF
376
377 C Print more debugging information
378 IF ( debugLevel.GE.debLevA ) THEN
379 IF ( newtonIter .EQ. SEAICEnewtonIterMax ) THEN
380 _BEGIN_MASTER( myThid )
381 WRITE(msgBuf,'(A,I10)')
382 & ' S/R SEAICE_JFNK: JFNK did not converge in timestep ',
383 & myIter+1
384 CALL PRINT_MESSAGE( msgBuf, standardMessageUnit,
385 & SQUEEZE_RIGHT, myThid )
386 _END_MASTER( myThid )
387 ENDIF
388 IF ( krylovFails .GT. 0 ) THEN
389 _BEGIN_MASTER( myThid )
390 WRITE(msgBuf,'(A,I4,A,I10)')
391 & ' S/R SEAICE_JFNK: FGMRES did not converge ',
392 & krylovFails, ' times in timestep ', myIter+1
393 CALL PRINT_MESSAGE( msgBuf, standardMessageUnit,
394 & SQUEEZE_RIGHT, myThid )
395 _END_MASTER( myThid )
396 ENDIF
397 _BEGIN_MASTER( myThid )
398 WRITE(msgBuf,'(A,I6,A,I10)')
399 & ' S/R SEAICE_JFNK: Total number FGMRES iterations = ',
400 & totalKrylovItersLoc, ' in timestep ', myIter+1
401 CALL PRINT_MESSAGE( msgBuf, standardMessageUnit,
402 & SQUEEZE_RIGHT, myThid )
403 _END_MASTER( myThid )
404 ENDIF
405
406 #endif /* SEAICE_ALLOW_DYNAMICS and SEAICE_CGRID and SEAICE_ALLOW_JFNK */
407
408 RETURN
409 END

  ViewVC Help
Powered by ViewVC 1.1.22