forked from kcroker/Gadget-2.0.7-ngravs
-
Notifications
You must be signed in to change notification settings - Fork 0
/
hydra.c
570 lines (478 loc) · 15.4 KB
/
hydra.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <mpi.h>
#include <gsl/gsl_math.h>
#include "allvars.h"
#include "proto.h"
/*! \file hydra.c
* \brief Computation of SPH forces and rate of entropy generation
*
* This file contains the "second SPH loop", where the SPH forces are
* computed, and where the rate of change of entropy due to the shock heating
* (via artificial viscosity) is computed.
*/
static double hubble_a, atime, hubble_a2, fac_mu, fac_vsic_fix, a3inv, fac_egy;
#ifdef PERIODIC
static double boxSize, boxHalf;
#ifdef LONG_X
static double boxSize_X, boxHalf_X;
#else
#define boxSize_X boxSize
#define boxHalf_X boxHalf
#endif
#ifdef LONG_Y
static double boxSize_Y, boxHalf_Y;
#else
#define boxSize_Y boxSize
#define boxHalf_Y boxHalf
#endif
#ifdef LONG_Z
static double boxSize_Z, boxHalf_Z;
#else
#define boxSize_Z boxSize
#define boxHalf_Z boxHalf
#endif
#endif
/*! This function is the driver routine for the calculation of hydrodynamical
* force and rate of change of entropy due to shock heating for all active
* particles .
*/
void hydro_force(void)
{
long long ntot, ntotleft;
int i, j, k, n, ngrp, maxfill, source, ndone;
int *nbuffer, *noffset, *nsend_local, *nsend, *numlist, *ndonelist;
int level, sendTask, recvTask, nexport, place;
double soundspeed_i;
double tstart, tend, sumt, sumcomm;
double timecomp = 0, timecommsumm = 0, timeimbalance = 0, sumimbalance;
MPI_Status status;
#ifdef PERIODIC
boxSize = All.BoxSize;
boxHalf = 0.5 * All.BoxSize;
#ifdef LONG_X
boxHalf_X = boxHalf * LONG_X;
boxSize_X = boxSize * LONG_X;
#endif
#ifdef LONG_Y
boxHalf_Y = boxHalf * LONG_Y;
boxSize_Y = boxSize * LONG_Y;
#endif
#ifdef LONG_Z
boxHalf_Z = boxHalf * LONG_Z;
boxSize_Z = boxSize * LONG_Z;
#endif
#endif
if(All.ComovingIntegrationOn)
{
/* Factors for comoving integration of hydro */
hubble_a = All.Omega0 / (All.Time * All.Time * All.Time)
+ (1 - All.Omega0 - All.OmegaLambda) / (All.Time * All.Time) + All.OmegaLambda;
hubble_a = All.Hubble * sqrt(hubble_a);
hubble_a2 = All.Time * All.Time * hubble_a;
fac_mu = pow(All.Time, 3 * (GAMMA - 1) / 2) / All.Time;
fac_egy = pow(All.Time, 3 * (GAMMA - 1));
fac_vsic_fix = hubble_a * pow(All.Time, 3 * GAMMA_MINUS1);
a3inv = 1 / (All.Time * All.Time * All.Time);
atime = All.Time;
}
else
hubble_a = hubble_a2 = atime = fac_mu = fac_vsic_fix = a3inv = fac_egy = 1.0;
/* `NumSphUpdate' gives the number of particles on this processor that want a force update */
for(n = 0, NumSphUpdate = 0; n < N_gas; n++)
{
if(P[n].Ti_endstep == All.Ti_Current)
NumSphUpdate++;
}
numlist = malloc(NTask * sizeof(int) * NTask);
MPI_Allgather(&NumSphUpdate, 1, MPI_INT, numlist, 1, MPI_INT, MPI_COMM_WORLD);
for(i = 0, ntot = 0; i < NTask; i++)
ntot += numlist[i];
free(numlist);
noffset = malloc(sizeof(int) * NTask); /* offsets of bunches in common list */
nbuffer = malloc(sizeof(int) * NTask);
nsend_local = malloc(sizeof(int) * NTask);
nsend = malloc(sizeof(int) * NTask * NTask);
ndonelist = malloc(sizeof(int) * NTask);
i = 0; /* first particle for this task */
ntotleft = ntot; /* particles left for all tasks together */
while(ntotleft > 0)
{
for(j = 0; j < NTask; j++)
nsend_local[j] = 0;
/* do local particles and prepare export list */
tstart = second();
for(nexport = 0, ndone = 0; i < N_gas && nexport < All.BunchSizeHydro - NTask; i++)
if(P[i].Ti_endstep == All.Ti_Current)
{
ndone++;
for(j = 0; j < NTask; j++)
Exportflag[j] = 0;
hydro_evaluate(i, 0);
for(j = 0; j < NTask; j++)
{
if(Exportflag[j])
{
for(k = 0; k < 3; k++)
{
HydroDataIn[nexport].Pos[k] = P[i].Pos[k];
HydroDataIn[nexport].Vel[k] = SphP[i].VelPred[k];
}
HydroDataIn[nexport].Hsml = SphP[i].Hsml;
HydroDataIn[nexport].Mass = P[i].Mass;
HydroDataIn[nexport].DhsmlDensityFactor = SphP[i].DhsmlDensityFactor;
HydroDataIn[nexport].Density = SphP[i].Density;
HydroDataIn[nexport].Pressure = SphP[i].Pressure;
HydroDataIn[nexport].Timestep = P[i].Ti_endstep - P[i].Ti_begstep;
/* calculation of F1 */
soundspeed_i = sqrt(GAMMA * SphP[i].Pressure / SphP[i].Density);
HydroDataIn[nexport].F1 = fabs(SphP[i].DivVel) /
(fabs(SphP[i].DivVel) + SphP[i].CurlVel +
0.0001 * soundspeed_i / SphP[i].Hsml / fac_mu);
HydroDataIn[nexport].Index = i;
HydroDataIn[nexport].Task = j;
nexport++;
nsend_local[j]++;
}
}
}
tend = second();
timecomp += timediff(tstart, tend);
qsort(HydroDataIn, nexport, sizeof(struct hydrodata_in), hydro_compare_key);
for(j = 1, noffset[0] = 0; j < NTask; j++)
noffset[j] = noffset[j - 1] + nsend_local[j - 1];
tstart = second();
MPI_Allgather(nsend_local, NTask, MPI_INT, nsend, NTask, MPI_INT, MPI_COMM_WORLD);
tend = second();
timeimbalance += timediff(tstart, tend);
/* now do the particles that need to be exported */
for(level = 1; level < (1 << PTask); level++)
{
tstart = second();
for(j = 0; j < NTask; j++)
nbuffer[j] = 0;
for(ngrp = level; ngrp < (1 << PTask); ngrp++)
{
maxfill = 0;
for(j = 0; j < NTask; j++)
{
if((j ^ ngrp) < NTask)
if(maxfill < nbuffer[j] + nsend[(j ^ ngrp) * NTask + j])
maxfill = nbuffer[j] + nsend[(j ^ ngrp) * NTask + j];
}
if(maxfill >= All.BunchSizeHydro)
break;
sendTask = ThisTask;
recvTask = ThisTask ^ ngrp;
if(recvTask < NTask)
{
if(nsend[ThisTask * NTask + recvTask] > 0 || nsend[recvTask * NTask + ThisTask] > 0)
{
/* get the particles */
MPI_Sendrecv(&HydroDataIn[noffset[recvTask]],
nsend_local[recvTask] * sizeof(struct hydrodata_in), MPI_BYTE,
recvTask, TAG_HYDRO_A,
&HydroDataGet[nbuffer[ThisTask]],
nsend[recvTask * NTask + ThisTask] * sizeof(struct hydrodata_in), MPI_BYTE,
recvTask, TAG_HYDRO_A, MPI_COMM_WORLD, &status);
}
}
for(j = 0; j < NTask; j++)
if((j ^ ngrp) < NTask)
nbuffer[j] += nsend[(j ^ ngrp) * NTask + j];
}
tend = second();
timecommsumm += timediff(tstart, tend);
/* now do the imported particles */
tstart = second();
for(j = 0; j < nbuffer[ThisTask]; j++)
hydro_evaluate(j, 1);
tend = second();
timecomp += timediff(tstart, tend);
/* do a block to measure imbalance */
tstart = second();
MPI_Barrier(MPI_COMM_WORLD);
tend = second();
timeimbalance += timediff(tstart, tend);
/* get the result */
tstart = second();
for(j = 0; j < NTask; j++)
nbuffer[j] = 0;
for(ngrp = level; ngrp < (1 << PTask); ngrp++)
{
maxfill = 0;
for(j = 0; j < NTask; j++)
{
if((j ^ ngrp) < NTask)
if(maxfill < nbuffer[j] + nsend[(j ^ ngrp) * NTask + j])
maxfill = nbuffer[j] + nsend[(j ^ ngrp) * NTask + j];
}
if(maxfill >= All.BunchSizeHydro)
break;
sendTask = ThisTask;
recvTask = ThisTask ^ ngrp;
if(recvTask < NTask)
{
if(nsend[ThisTask * NTask + recvTask] > 0 || nsend[recvTask * NTask + ThisTask] > 0)
{
/* send the results */
MPI_Sendrecv(&HydroDataResult[nbuffer[ThisTask]],
nsend[recvTask * NTask + ThisTask] * sizeof(struct hydrodata_out),
MPI_BYTE, recvTask, TAG_HYDRO_B,
&HydroDataPartialResult[noffset[recvTask]],
nsend_local[recvTask] * sizeof(struct hydrodata_out),
MPI_BYTE, recvTask, TAG_HYDRO_B, MPI_COMM_WORLD, &status);
/* add the result to the particles */
for(j = 0; j < nsend_local[recvTask]; j++)
{
source = j + noffset[recvTask];
place = HydroDataIn[source].Index;
for(k = 0; k < 3; k++)
SphP[place].HydroAccel[k] += HydroDataPartialResult[source].Acc[k];
SphP[place].DtEntropy += HydroDataPartialResult[source].DtEntropy;
if(SphP[place].MaxSignalVel < HydroDataPartialResult[source].MaxSignalVel)
SphP[place].MaxSignalVel = HydroDataPartialResult[source].MaxSignalVel;
}
}
}
for(j = 0; j < NTask; j++)
if((j ^ ngrp) < NTask)
nbuffer[j] += nsend[(j ^ ngrp) * NTask + j];
}
tend = second();
timecommsumm += timediff(tstart, tend);
level = ngrp - 1;
}
MPI_Allgather(&ndone, 1, MPI_INT, ndonelist, 1, MPI_INT, MPI_COMM_WORLD);
for(j = 0; j < NTask; j++)
ntotleft -= ndonelist[j];
}
free(ndonelist);
free(nsend);
free(nsend_local);
free(nbuffer);
free(noffset);
/* do final operations on results */
tstart = second();
for(i = 0; i < N_gas; i++)
if(P[i].Ti_endstep == All.Ti_Current)
{
SphP[i].DtEntropy *= GAMMA_MINUS1 / (hubble_a2 * pow(SphP[i].Density, GAMMA_MINUS1));
#ifdef SPH_BND_PARTICLES
if(P[i].ID == 0)
{
SphP[i].DtEntropy = 0;
for(k = 0; k < 3; k++)
SphP[i].HydroAccel[k] = 0;
}
#endif
}
tend = second();
timecomp += timediff(tstart, tend);
/* collect some timing information */
MPI_Reduce(&timecomp, &sumt, 1, MPI_DOUBLE, MPI_SUM, 0, MPI_COMM_WORLD);
MPI_Reduce(&timecommsumm, &sumcomm, 1, MPI_DOUBLE, MPI_SUM, 0, MPI_COMM_WORLD);
MPI_Reduce(&timeimbalance, &sumimbalance, 1, MPI_DOUBLE, MPI_SUM, 0, MPI_COMM_WORLD);
if(ThisTask == 0)
{
All.CPU_HydCompWalk += sumt / NTask;
All.CPU_HydCommSumm += sumcomm / NTask;
All.CPU_HydImbalance += sumimbalance / NTask;
}
}
/*! This function is the 'core' of the SPH force computation. A target
* particle is specified which may either be local, or reside in the
* communication buffer.
*/
void hydro_evaluate(int target, int mode)
{
int j, k, n, timestep, startnode, numngb;
FLOAT *pos, *vel;
FLOAT mass, h_i, dhsmlDensityFactor, rho, pressure, f1, f2;
double acc[3], dtEntropy, maxSignalVel;
double dx, dy, dz, dvx, dvy, dvz;
double h_i2, hinv, hinv4;
double p_over_rho2_i, p_over_rho2_j, soundspeed_i, soundspeed_j;
double hfc, dwk_i, vdotr, vdotr2, visc, mu_ij, rho_ij, vsig;
double h_j, dwk_j, r, r2, u, hfc_visc;
#ifndef NOVISCOSITYLIMITER
double dt;
#endif
if(mode == 0)
{
pos = P[target].Pos;
vel = SphP[target].VelPred;
h_i = SphP[target].Hsml;
mass = P[target].Mass;
dhsmlDensityFactor = SphP[target].DhsmlDensityFactor;
rho = SphP[target].Density;
pressure = SphP[target].Pressure;
timestep = P[target].Ti_endstep - P[target].Ti_begstep;
soundspeed_i = sqrt(GAMMA * pressure / rho);
f1 = fabs(SphP[target].DivVel) /
(fabs(SphP[target].DivVel) + SphP[target].CurlVel +
0.0001 * soundspeed_i / SphP[target].Hsml / fac_mu);
}
else
{
pos = HydroDataGet[target].Pos;
vel = HydroDataGet[target].Vel;
h_i = HydroDataGet[target].Hsml;
mass = HydroDataGet[target].Mass;
dhsmlDensityFactor = HydroDataGet[target].DhsmlDensityFactor;
rho = HydroDataGet[target].Density;
pressure = HydroDataGet[target].Pressure;
timestep = HydroDataGet[target].Timestep;
soundspeed_i = sqrt(GAMMA * pressure / rho);
f1 = HydroDataGet[target].F1;
}
/* initialize variables before SPH loop is started */
acc[0] = acc[1] = acc[2] = dtEntropy = 0;
maxSignalVel = 0;
p_over_rho2_i = pressure / (rho * rho) * dhsmlDensityFactor;
h_i2 = h_i * h_i;
/* Now start the actual SPH computation for this particle */
startnode = All.MaxPart;
do
{
numngb = ngb_treefind_pairs(&pos[0], h_i, &startnode);
for(n = 0; n < numngb; n++)
{
j = Ngblist[n];
dx = pos[0] - P[j].Pos[0];
dy = pos[1] - P[j].Pos[1];
dz = pos[2] - P[j].Pos[2];
#ifdef PERIODIC /* find the closest image in the given box size */
if(dx > boxHalf_X)
dx -= boxSize_X;
if(dx < -boxHalf_X)
dx += boxSize_X;
if(dy > boxHalf_Y)
dy -= boxSize_Y;
if(dy < -boxHalf_Y)
dy += boxSize_Y;
if(dz > boxHalf_Z)
dz -= boxSize_Z;
if(dz < -boxHalf_Z)
dz += boxSize_Z;
#endif
r2 = dx * dx + dy * dy + dz * dz;
h_j = SphP[j].Hsml;
if(r2 < h_i2 || r2 < h_j * h_j)
{
r = sqrt(r2);
if(r > 0)
{
p_over_rho2_j = SphP[j].Pressure / (SphP[j].Density * SphP[j].Density);
soundspeed_j = sqrt(GAMMA * p_over_rho2_j * SphP[j].Density);
dvx = vel[0] - SphP[j].VelPred[0];
dvy = vel[1] - SphP[j].VelPred[1];
dvz = vel[2] - SphP[j].VelPred[2];
vdotr = dx * dvx + dy * dvy + dz * dvz;
if(All.ComovingIntegrationOn)
vdotr2 = vdotr + hubble_a2 * r2;
else
vdotr2 = vdotr;
if(r2 < h_i2)
{
hinv = 1.0 / h_i;
#ifndef TWODIMS
hinv4 = hinv * hinv * hinv * hinv;
#else
hinv4 = hinv * hinv * hinv / boxSize_Z;
#endif
u = r * hinv;
if(u < 0.5)
dwk_i = hinv4 * u * (KERNEL_COEFF_3 * u - KERNEL_COEFF_4);
else
dwk_i = hinv4 * KERNEL_COEFF_6 * (1.0 - u) * (1.0 - u);
}
else
{
dwk_i = 0;
}
if(r2 < h_j * h_j)
{
hinv = 1.0 / h_j;
#ifndef TWODIMS
hinv4 = hinv * hinv * hinv * hinv;
#else
hinv4 = hinv * hinv * hinv / boxSize_Z;
#endif
u = r * hinv;
if(u < 0.5)
dwk_j = hinv4 * u * (KERNEL_COEFF_3 * u - KERNEL_COEFF_4);
else
dwk_j = hinv4 * KERNEL_COEFF_6 * (1.0 - u) * (1.0 - u);
}
else
{
dwk_j = 0;
}
if(soundspeed_i + soundspeed_j > maxSignalVel)
maxSignalVel = soundspeed_i + soundspeed_j;
if(vdotr2 < 0) /* ... artificial viscosity */
{
mu_ij = fac_mu * vdotr2 / r; /* note: this is negative! */
vsig = soundspeed_i + soundspeed_j - 3 * mu_ij;
if(vsig > maxSignalVel)
maxSignalVel = vsig;
rho_ij = 0.5 * (rho + SphP[j].Density);
f2 =
fabs(SphP[j].DivVel) / (fabs(SphP[j].DivVel) + SphP[j].CurlVel +
0.0001 * soundspeed_j / fac_mu / SphP[j].Hsml);
visc = 0.25 * All.ArtBulkViscConst * vsig * (-mu_ij) / rho_ij * (f1 + f2);
/* .... end artificial viscosity evaluation */
#ifndef NOVISCOSITYLIMITER
/* make sure that viscous acceleration is not too large */
dt = imax(timestep, (P[j].Ti_endstep - P[j].Ti_begstep)) * All.Timebase_interval;
if(dt > 0 && (dwk_i + dwk_j) < 0)
{
visc = dmin(visc, 0.5 * fac_vsic_fix * vdotr2 /
(0.5 * (mass + P[j].Mass) * (dwk_i + dwk_j) * r * dt));
}
#endif
}
else
visc = 0;
p_over_rho2_j *= SphP[j].DhsmlDensityFactor;
hfc_visc = 0.5 * P[j].Mass * visc * (dwk_i + dwk_j) / r;
hfc = hfc_visc + P[j].Mass * (p_over_rho2_i * dwk_i + p_over_rho2_j * dwk_j) / r;
acc[0] -= hfc * dx;
acc[1] -= hfc * dy;
acc[2] -= hfc * dz;
dtEntropy += 0.5 * hfc_visc * vdotr2;
}
}
}
}
while(startnode >= 0);
/* Now collect the result at the right place */
if(mode == 0)
{
for(k = 0; k < 3; k++)
SphP[target].HydroAccel[k] = acc[k];
SphP[target].DtEntropy = dtEntropy;
SphP[target].MaxSignalVel = maxSignalVel;
}
else
{
for(k = 0; k < 3; k++)
HydroDataResult[target].Acc[k] = acc[k];
HydroDataResult[target].DtEntropy = dtEntropy;
HydroDataResult[target].MaxSignalVel = maxSignalVel;
}
}
/*! This is a comparison kernel for a sort routine, which is used to group
* particles that are going to be exported to the same CPU.
*/
int hydro_compare_key(const void *a, const void *b)
{
if(((struct hydrodata_in *) a)->Task < (((struct hydrodata_in *) b)->Task))
return -1;
if(((struct hydrodata_in *) a)->Task > (((struct hydrodata_in *) b)->Task))
return +1;
return 0;
}