anneal.cc 32.8 KB
Newer Older
1 2 3 4 5 6 7 8
/*
 * EMULAB-COPYRIGHT
 * Copyright (c) 2003 University of Utah and the Flux Group.
 * All rights reserved.
 */

#include "anneal.h"

9 10 11 12 13 14 15
#include "virtual.h"
#include "maps.h"
#include "common.h"
#include "score.h"
#include "solution.h"
#include "vclass.h"

16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33
/*
 * Internal variables
 */
// These variables store the best solution.
node_map absassignment;		// assignment field of vnode
assigned_map absassigned;	// assigned field of vnode
type_map abstypes;		// type field of vnode

// Map of virtual node name to its vertex descriptor.
name_vvertex_map vname2vertex;

// This is a vector of all the nodes in the top file.  It's used
// to randomly choose nodes.
vvertex_vector virtual_nodes;

// Map of physical node name to its vertex descriptor.
name_pvertex_map pname2vertex;
  
Robert Ricci's avatar
Robert Ricci committed
34
// Map of virtual node name to the physical node name it's fixed to.
35 36 37 38
// The domain is the set of all fixed virtual nodes and the range is
// the set of all fixed physical nodes.
name_name_map fixed_nodes;

Robert Ricci's avatar
Robert Ricci committed
39 40 41 42 43
// Map of virtual node name to the physical node name that we should
// start the virtual node on. However, unlike fixed nodes, assign is
// allowed to move these.
name_name_map node_hints;

44 45 46 47 48
// From assign.cc
#ifdef GNUPLOT_OUTPUT
extern FILE *scoresout, *tempout, *deltaout;
#endif

49 50 51 52 53 54 55 56 57 58 59 60
// Determines whether to accept a change of score difference 'change' at
// temperature 'temperature'.
inline int accept(double change, double temperature)
{
  double p;
  int r;

  if (change == 0) {
    p = 1000 * temperature / temp_prob;
  } else {
    p = expf(change/temperature) * 1000;
  }
61
  r = random() % 1000;
62 63 64 65 66 67
  if (r < p) {
    return 1;
  }
  return 0;
}

68 69 70 71
/*
 * This overly-verbose function returns true if it's okay to map vn to pn,
 * false otherwise
 */
72
inline bool pnode_is_match(tb_vnode *vn, tb_pnode *pn) {
73 74 75 76 77 78 79 80 81 82
  // Find the type record for this type
  tb_pnode::types_map::iterator mit = pn->types.find(vn->type);
  if (mit == pn->types.end()) {
    // The node doesn't even have this type, we can exit early
    return false;
  }

  bool matched = false;
  tb_pnode::type_record *tr = mit->second;
  if (tr->is_static) {
83 84
    if ((tr->current_load + vn->typecount) > tr->max_load) {
      // This would put us over its max load
85
      if (allow_overload && (tr->max_load > 1)) {
86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101
	// That's okay, we're allowing overload
	matched = true;
      } else {
	// Nope, it's full
	matched = false;
      }
    } else {
      // Plenty of room for us
      matched = true;
    }
  } else { // the type is not static
    if (pn->typed) {
      if (pn->current_type.compare(vn->type)) {
	// Failure - the pnode has a type, and it isn't ours
	matched = false;
      } else {
102
	if ((pn->current_type_record->current_load + vn->typecount) >
103
	    pn->current_type_record->max_load) {
104
	  // This would put us over its max load
105 106 107
	  //if (allow_overload && (tr->max_load > 1) &&
	  //    ((pn->current_type_record->current_load + vn->typecount) <
	  //    (pn->current_type_record->max_load + 2))) {
108
	  if (allow_overload && (tr->max_load > 1)) {
109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125
	    // That's okay, we're allowing overload
	    matched = true;
	  } else {
	    // Failure - the type is right, but the pnode is full
	    matched = false;
	  }
	} else {
	  // It's under its max load, we can fit in
	  matched = true;
	}
      }
    } else {
      // pnode doesn't have a type
      matched = true;
    }
  }

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
  // Check for 'local' desires - the reason we take the time to do this here is
  // that they are actually, in many ways, like types with vn->typecount > 1.
  if (matched && !vn->desires.empty()) {
    tb_vnode::desires_map::iterator desire_it;
    for (desire_it = vn->desires.begin();
	desire_it != vn->desires.end();
	desire_it++) {
      if (desire_it->first[0] != '?') {
	continue;
      }
      if (desire_it->first[1] != '+') {
	continue;
      }
      tb_pnode::features_map::iterator feature_it =
	pn->features.find(desire_it->first);
      if (feature_it == pn->features.end()) {
	matched = false;
	break;
      }
      // If we are allowing overloading, do so only to a limited degree
      if (allow_overload) {
	if ((feature_it->second < desire_it->second)
	    && (feature_it->second - desire_it->second)
	        < (desire_it->second * 2)) {
	  matched = false;
	  break;
	}
      } else {
	// No overloading, and this would put us over the limit
	if (feature_it->second < desire_it->second) {
	  matched = false;
	  break;
	}
      }
    }
  }

163 164 165
  return matched;
}

166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184
/*
 * Finds a pnode which:
 * 1) One of the vnode's neighbors is mapped to
 * 2) Satisifies the usual pnode mapping constraints
 * 3) The vnode is not already mapped to
 */
tb_pnode *find_pnode_connected(vvertex vv, tb_vnode *vn) {

  //cerr << "find_pnode_connected(" << vn->name << ") called" << endl;

  // We make a list of all neighboring vnodes so that we can go through
  // them in random order
  vector<vedge> visit_order(out_degree(vv,VG));
  voedge_iterator vedge_it,end_vedge_it;
  tie(vedge_it,end_vedge_it) = out_edges(vv,VG);	    
  for (int i = 0; vedge_it != end_vedge_it; vedge_it++, i++) {
    visit_order[i] = *vedge_it;
  }
  for (int i = 0; i < visit_order.size(); i++) {
185 186
	int i1 = random() % visit_order.size();
	int i2 = random() % visit_order.size();
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
	vedge tmp = visit_order[i1];
	visit_order[i1] = visit_order[i2];
	visit_order[i2] = tmp;
  }
  for (int i = 0; i < visit_order.size(); i++) {
    vvertex neighbor_vv = target(visit_order[i],VG);
    tb_vnode *neighbor_vn = get(vvertex_pmap,neighbor_vv);
    //cerr << "    trying " << neighbor_vn->name << endl;
    // Skip any that aren't assigned
    if (!neighbor_vn->assigned) {
      //cerr << "        not assigned" << endl;
      continue;
    }

    // Skip any that are assigned to the same pnode we are
    if (neighbor_vn->assignment == vn->assignment) {
      //cerr << "        same assignment" << endl;
      continue;
    }

    // Check to make sure that our vn can map to the neibor's assigment
    tb_pnode *neighbor_pnode = get(pvertex_pmap,neighbor_vn->assignment);
    //cerr << "        neighbor on " << neighbor_pnode->name << endl;
    if (pnode_is_match(vn,neighbor_pnode)) {
      //cerr << "        good" << endl;
      //cerr << "    worked" << endl;
      return neighbor_pnode;
    }
    //cerr << "        doesn't match" << endl;
  }

  //cerr << "    failed" << endl;
  return NULL;
}

222 223 224 225 226 227 228 229 230 231
tb_pnode *find_pnode(tb_vnode *vn)
{
#ifdef PER_VNODE_TT
  tt_entry tt = vnode_type_table[vn->name];
#else
  tt_entry tt = type_table[vn->type];
#endif
  int num_types = tt.first;
  pclass_vector *acceptable_types = tt.second;
  
232
  tb_pnode *newpnode = NULL;
233 234
  
  //cerr << "Node is " << vn->name << " First = " << first << endl;
235

236 237 238 239
  // Randomize the order in which we go through the list of acceptable pclasses
  // We do this by making a randomly-ordered list of indicies into the
  // acceptable_types vector
  vector<int> traversal_order(num_types);
240
  for (int i = 0; i < num_types; i++) {
241 242 243
	traversal_order[i] = i;
  }
  for (int i = 0; i < num_types; i++) {
244 245
	int i1 = random() % num_types;
	int i2 = random() % num_types;
246 247 248
	int tmp = traversal_order[i1];
	traversal_order[i1] = traversal_order[i2];
	traversal_order[i2] = tmp;
249
  }
250

251
  for (int i = 0; i < num_types; i++) {
252

253 254
    int index = traversal_order[i];
    tb_pclass *pclass = (*acceptable_types)[index];
255

256 257 258
    // Skip pclasses that have been disabled
    if (pclass->disabled) {
	  continue;
259
    }
260 261 262

#ifndef FIND_PNODE_SEARCH
    // If not searching for the pnode, just grab the front one
263
    newpnode = pclass->members[vn->type]->front();
264
#else
265 266 267 268 269
#ifdef PER_VNODE_TT
    // If using PER_VNODE_TT and vclasses, it's possible that there are
    // some pclasses in this node's type table that can't be used right now,
    // becuase they contain entires that don't contain the vnodes _current_
    // type
270
    if (pclass->members.find(vn->type) == pclass->members.end()) {
271 272 273
	continue;
    }
#endif
274

275 276
    list<tb_pnode*>::iterator it = pclass->members[vn->type]->L.begin();
    while (it != pclass->members[vn->type]->L.end()) {
277 278
	if (pnode_is_match(vn,*it)) {
	    break; 
Robert Ricci's avatar
Robert Ricci committed
279
	} else {
280
	    it++;
281 282
	}
    }
283
    if (it == pclass->members[vn->type]->L.end()) {
284 285 286 287
	newpnode = NULL;
    } else {
	newpnode = *it;
    }
288
#endif // FIND_PNODE_SEARCH
289 290
#ifdef PCLASS_DEBUG
    cerr << "Found pclass: " <<
291
      pclass->name << " and node " <<
292 293 294 295 296 297 298
      (newpnode == NULL ? "NULL" : newpnode->name) << "\n";
#endif
    if (newpnode != NULL) {
      RDEBUG(cout << " to " << newpnode->name << endl;)
      return newpnode;
    }
  }
299 300 301

  // Nope, didn't find one
  return NULL;
302 303
}

304 305 306
// We put the temperature outside the function so that external stuff, like
// status_report in assign.cc, can see it.
double temp;
307 308

/* When this is finished the state will reflect the best solution found. */
Robert Ricci's avatar
Robert Ricci committed
309
void anneal(bool scoring_selftest, double scale_neighborhood,
310
	double *initial_temperature, double use_connected_pnode_find)
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
{
  cout << "Annealing." << endl;

  double newscore = 0;
  double bestscore = 0;
 
  // The number of iterations that took place.
  iters = 0;
  iters_to_best = 0;
  int accepts = 0;
  
  double scorediff;

  int nnodes = num_vertices(VG);
  int npnodes = num_vertices(PG);
  int npclasses = pclasses.size();
  
  float cycles = CYCLES*(float)(nnodes + num_edges(VG) + PHYSICAL(npnodes));
  float optimal = OPTIMAL_SCORE(num_edges(VG),nnodes);
    
#ifdef STATS
  cout << "STATS_OPTIMAL = " << optimal << endl;
#endif

  int mintrans = (int)cycles;
  int trans;
  int naccepts = 20*(nnodes + PHYSICAL(npnodes));
  pvertex oldpos;
  bool oldassigned;
  int bestviolated;
  int num_fixed=0;
  double meltedtemp;
343
  temp = init_temp;
344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362
  double deltatemp, deltaavg;

  // Priority queue of unassigned virtual nodes.  Basically a fancy way
  // of randomly choosing a unassigned virtual node.  When nodes become
  // unassigned they are placed in the queue with a random priority.
  vvertex_int_priority_queue unassigned_nodes;

#ifdef VERBOSE
  cout << "Initialized to cycles="<<cycles<<" optimal="<<optimal<<" mintrans="
       << mintrans<<" naccepts="<<naccepts<< endl;
#endif

  /* Set up the initial counts */
  init_score();

  /* Set up fixed nodes */
  for (name_name_map::iterator fixed_it=fixed_nodes.begin();
       fixed_it!=fixed_nodes.end();++fixed_it) {
    if (vname2vertex.find((*fixed_it).first) == vname2vertex.end()) {
363
      cout << "Fixed node: " << (*fixed_it).first <<
364
	"does not exist." << endl;
365
      exit(EXIT_UNRETRYABLE);
366 367 368
    }
    vvertex vv = vname2vertex[(*fixed_it).first];
    if (pname2vertex.find((*fixed_it).second) == pname2vertex.end()) {
369
      cout << "Fixed node: " << (*fixed_it).second <<
370
	" not available." << endl;
371
      exit(EXIT_UNRETRYABLE);
372 373 374 375 376
    }
    pvertex pv = pname2vertex[(*fixed_it).second];
    tb_vnode *vn = get(vvertex_pmap,vv);
    tb_pnode *pn = get(pvertex_pmap,pv);
    if (vn->vclass != NULL) {
377
      cout << "Can not have fixed nodes be in a vclass!.\n";
378
      exit(EXIT_FATAL);
379
    }
380
    if (add_node(vv,pv,false,true) == 1) {
381
      cout << "Fixed node: Could not map " << vn->name <<
382
	" to " << pn->name << endl;
383
      exit(EXIT_UNRETRYABLE);
384 385 386 387 388
    }
    vn->fixed = true;
    num_fixed++;
  }

389 390 391 392
  // Subtract the number of fixed nodes from nnodes, since they don't really
  // count
  if (num_fixed) {
      cout << "Adjusting dificulty estimate for fixed nodes, " <<
393
	  (nnodes - num_fixed) << " remain.\n";
394 395
  }

396 397 398 399
  /* We'll check against this later to make sure that whe we've unmapped
   * everything, the score is the same */
  double initial_score = get_score();

Robert Ricci's avatar
Robert Ricci committed
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
  /*
   * Handle node hints - we do this _after_ we've figured out the initial
   * score, since, unlike fixed nodes, hints get unmapped before we do the
   * final mapping. Also, we ignore any hints for vnodes which have already
   * been assigned - they must have been fixed, and that over-rides the hint.
   */
  for (name_name_map::iterator hint_it=node_hints.begin();
       hint_it!=node_hints.end();++hint_it) {
    if (vname2vertex.find((*hint_it).first) == vname2vertex.end()) {
      cout << "Warning: Hinted node: " << (*hint_it).first <<
	"does not exist." << endl;
      continue;
    }
    vvertex vv = vname2vertex[(*hint_it).first];
    if (pname2vertex.find((*hint_it).second) == pname2vertex.end()) {
      cout << "Warning: Hinted node: " << (*hint_it).second <<
	" not available." << endl;
      continue;
    }
    pvertex pv = pname2vertex[(*hint_it).second];
    tb_vnode *vn = get(vvertex_pmap,vv);
    tb_pnode *pn = get(pvertex_pmap,pv);
    if (vn->assigned) {
      cout << "Warning: Skipping hint for node " << vn->name << ", which is "
	<< "fixed in place" << endl;
      continue;
    }
427
    if (add_node(vv,pv,false,false) == 1) {
Robert Ricci's avatar
Robert Ricci committed
428 429 430 431 432 433
      cout << "Warning: Hinted node: Could not map " << vn->name <<
	" to " << pn->name << endl;
      continue;
    }
  }

434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453
  bestscore = get_score();
  bestviolated = violated;

#ifdef VERBOSE
  cout << "Problem started with score "<<bestscore<<" and "<< violated
       << " violations." << endl;
#endif

  absbest = bestscore;
  absbestviolated = bestviolated;

  vvertex_iterator vit,veit;
  tie(vit,veit) = vertices(VG);
  for (;vit!=veit;++vit) {
    tb_vnode *vn = get(vvertex_pmap,*vit);
    absassigned[*vit] = vn->assigned;
    if (vn->assigned) {
      absassignment[*vit] = vn->assignment;
      abstypes[*vit] = vn->type;
    } else {
454
      unassigned_nodes.push(vvertex_int_pair(*vit,random()));
455 456 457 458
    }
  }

  int neighborsize;
459
  neighborsize = (nnodes - num_fixed) * npclasses;
460 461 462
  if (neighborsize < min_neighborhood_size) {
    neighborsize = min_neighborhood_size;
  }
463 464 465 466 467

  // Allow scaling of the neighborhood size, so we can make assign try harder
  // (or less hard)
  neighborsize = (int)(neighborsize * scale_neighborhood);

468 469 470 471
#ifdef CHILL
  double scores[neighborsize];
#endif

472
  if (num_fixed >= nnodes) {
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
    cout << "All nodes are fixed.  No annealing." << endl;
    goto DONE;
  }
  
  // Annealing loop!
  vvertex vv;
  tb_vnode *vn;

  // Crap added by ricci
  bool melting;
  int nincreases, ndecreases;
  double avgincrease;
  double avgscore;
  double initialavg;
  double stddev;
  bool finished;
  bool forcerevert;
  finished = forcerevert = false;
  int tsteps;
  int mintsteps;
  double meltstart;

#define MAX_AVG_HIST 16
  double avghist[MAX_AVG_HIST];
  int hstart, nhist;
  hstart = nhist = 0;
  double lasttemp;
  double smoothedavg, lastsmoothed;
  lastsmoothed = 500000.0f;
  lasttemp = 5000.0f;
  int melttrials;
  melttrials = 0;

  bool finishedonce;
  finishedonce = false;

  tsteps = 0;
  mintsteps = MAX_AVG_HIST;
  tsteps = 0;
  mintsteps = MAX_AVG_HIST;
  tsteps = 0;
  mintsteps = MAX_AVG_HIST;

  // Make sure the last two don't prevent us from running!
  avgscore = initialavg = 1.0;

  stddev = 0;

#ifdef MELT
Robert Ricci's avatar
Robert Ricci committed
522 523 524 525 526 527 528
  if (initial_temperature == NULL) {
      melting = true;
  } else {
      melting = false;
      temp = *initial_temperature;
      cout << "Starting with initial temperature " << temp << endl;
  }
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
#ifdef TIME_TARGET
  meltstart = used_time();
#endif
#else
  melting = false;
#endif

  melt_trans = neighborsize;
#ifdef EPSILON_TERMINATE
  while(1) {
#else
  while (temp >= temp_stop) {
#endif
#ifdef VERBOSE
    cout << "Temperature:  " << temp << " AbsBest: " << absbest <<
      " (" << absbestviolated << ")" << endl;
#endif
    trans = 0;
    accepts = 0;
    nincreases = ndecreases = 0;
    avgincrease = 0.0;
    avgscore = bestscore;
#ifdef CHILL
    scores[0] = bestscore;
#endif

555 556
    // Adjust the number of transitions we're going to do based on the number
    // of pclasses that are actually 'in play'
557 558
    int transitions = (int)(neighborsize *
      (count_enabled_pclasses() *1.0 / pclasses.size()));
559 560
    assert(transitions <= neighborsize);

561 562 563 564 565 566
    if (melting) {
      cout << "Doing melting run" << endl;
    }

    while ((melting && (trans < melt_trans))
#ifdef NEIGHBOR_LENGTH
567
	    || (trans < transitions)) {
568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587
#else
	    || (!melting && (trans < mintrans && accepts < naccepts))) {
#endif

#ifdef STATS
      cout << "STATS temp:" << temp << " score:" << get_score() <<
	" violated:" << violated << " trans:" << trans <<
	" accepts:" << accepts << " current_time:" <<
	used_time() << endl;
#endif 
      pvertex newpos;
      trans++;
      iters++;

      bool freednode = false;
      if (! unassigned_nodes.empty()) {
	vv = unassigned_nodes.top().first;
	assert(!get(vvertex_pmap,vv)->assigned);
	unassigned_nodes.pop();
      } else {
588
	int start = random()%nnodes;
589 590 591 592 593 594 595 596 597 598 599
	int choice = start;
	while (get(vvertex_pmap,virtual_nodes[choice])->fixed) {
	  choice = (choice +1) % nnodes;
	  if (choice == start) {
	      choice = -1;
	      break;
	  }
	}
	if (choice >= 0) {
	    vv = virtual_nodes[choice];
	} else {
600
	    cout << "**** Error, unable to find any non-fixed nodes" << endl;
601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624
	    goto DONE;
	}
      }
      
      vn = get(vvertex_pmap,vv);
      RDEBUG(cout << "Reassigning " << vn->name << endl;)
      oldassigned = vn->assigned;
      oldpos = vn->assignment;
      
#ifdef FREE_IMMEDIATELY
      if (oldassigned) {
	remove_node(vv);
	RDEBUG(cout << "Freeing up " << vn->name << endl;)
      }
#endif
      
      if (vn->vclass != NULL) {
	vn->type = vn->vclass->choose_type();
#ifdef SCORE_DEBUG
	cerr << "vclass " << vn->vclass->name  << ": choose type for " <<
	    vn->name << " = " << vn->type << " dominant = " <<
	    vn->vclass->dominant << endl;
#endif
      }
625 626 627 628

      // Actually find a pnode
      tb_pnode *newpnode = NULL;
      if ((use_connected_pnode_find != 0)
629
	  && ((random() % 1000) < (use_connected_pnode_find * 1000))) {
630 631 632 633 634
	newpnode = find_pnode_connected(vv,vn);
      }
      if (newpnode == NULL) {
	newpnode = find_pnode(vn);
      }
635
#ifndef FREE_IMMEDIATELY
636 637
      if (oldassigned) {
	RDEBUG(cout << "removing: !lan, oldassigned" << endl;)
638
	  remove_node(vv);
639
      }
640
#endif
641 642
      if (newpnode == NULL) {
	// We're not going to be re-assigning this one
643
#ifndef SMART_UNMAP
644
	unassigned_nodes.push(vvertex_int_pair(vv,random()));
645
#endif
646
	// need to free up nodes
647
#ifdef SMART_UNMAP
648 649 650 651 652 653 654 655 656 657 658
	// XXX: Should probably randomize this
	// XXX: Add support for not using PER_VNODE_TT
	// XXX: Not very robust

	freednode = true;

	tt_entry tt = vnode_type_table[vn->name];
	int size = tt.first;
	pclass_vector *acceptable_types = tt.second;
	// Find a node to kick out
	bool foundnode = false;
659
	int offi = random();
660 661 662 663 664 665 666 667 668
	int index;
	for (int i = 0; i < size; i++) {
	  index = (i + offi) % size;
	  if ((*acceptable_types)[index]->used_members.find(vn->type) ==
	      (*acceptable_types)[index]->used_members.end()) {
	    continue;
	  }
	  if ((*acceptable_types)[index]->used_members[vn->type]->size() == 0) {
	    continue;
669
	  }
670 671 672
	  foundnode = true;
	  break;
	}
673

674 675
	if (foundnode) {
	  assert((*acceptable_types)[index]->used_members[vn->type]->size());
676 677
	  tb_pclass::tb_pnodeset::iterator it =
	    (*acceptable_types)[index]->used_members[vn->type]->begin();
678
	  int j = random() %
679
	    (*acceptable_types)[index]->used_members[vn->type]->size();
680 681 682 683 684
	  while (j > 0) {
	    it++;
	    j--;
	  }
	  tb_vnode_set::iterator it2 = (*it)->assigned_nodes.begin();
685
	  int k = random() % (*it)->assigned_nodes.size();
686 687 688
	  while (k > 0) {
	    it2++;
	    k--;
689
	  }
690 691 692 693 694 695
	  tb_vnode *kickout = *it2;
	  assert(kickout->assigned);
	  vvertex toremove = vname2vertex[kickout->name];
	  newpnode = *it;
	  remove_node(toremove);
	  unassigned_nodes.push(vvertex_int_pair(toremove,
696
		random()));
697 698 699
	} else {
	  cerr << "Failed to find a replacement!" << endl;
	}
700 701

#else
702
	int start = random()%nnodes;
703
	int toremove = start;
704 705 706
#ifdef SMART_UNMAP

#ifdef PER_VNODE_TT
707
	  tt_entry tt = vnode_type_table[vn->name];
708 709 710 711 712 713
#else
	  tt_entry tt = type_table[vn->type];
#endif
	  pclass_vector *acceptable_types = tt.second;

	  while (1) {
714 715 716 717 718 719 720 721 722 723 724
	    bool keepgoing = false;
	    if (get(vvertex_pmap,virtual_nodes[toremove])->fixed) {
	      keepgoing = true;
	    } else if (! get(vvertex_pmap,virtual_nodes[toremove])->assigned) {
	      keepgoing = true;
	    } else {
	      pvertex pv = get(vvertex_pmap,virtual_nodes[toremove])->assignment;
	      tb_pnode *pn = get(pvertex_pmap,pv);
	      int j;
	      for (j = 0; j < acceptable_types->size(); j++) {
		if ((*acceptable_types)[j] == pn->my_class) {
725
		  break;
726 727 728 729
		}
	      }
	      if (j == acceptable_types->size()) {
		keepgoing = true;
730
	      }
731 732 733 734 735 736
	    }

	    if (!keepgoing) {
	      break;
	    }

737
#else
738 739
	    while (get(vvertex_pmap,virtual_nodes[toremove])->fixed ||
		(! get(vvertex_pmap,virtual_nodes[toremove])->assigned)) {
740 741 742
#endif
	      toremove = (toremove +1) % nnodes;
	      if (toremove == start) {
743 744
		toremove = -1;
		break;
745
	      }
746 747
	    }
	    if (toremove >= 0) {
748
	      RDEBUG(cout << "removing: freeing up nodes" << endl;)
749
		remove_node(virtual_nodes[toremove]);
750
	      unassigned_nodes.push(vvertex_int_pair(virtual_nodes[toremove],
751
		    random()));
752 753
	    }
	    continue;
754 755
#endif /* SMART_UNMAP */
#ifndef SMART_UNMAP
756
	  } else {
757
#else
758
	  }
759 760
#endif
	  if (newpnode != NULL) {
761 762 763 764 765 766
	    newpos = pnode2vertex[newpnode];
	    if (scoring_selftest) {
	      // Run a little test here - see if the score we get by adding
	      // this node, then removing it, is the same one we would have
	      // gotten otherwise
	      double oldscore = get_score();
767
	      int oldviolated = violated;
Robert Ricci's avatar
Robert Ricci committed
768
	      double tempscore;
769
	      int tempviolated;
770
	      if (!add_node(vv,newpos,false,false)) {
Robert Ricci's avatar
Robert Ricci committed
771
		tempscore = get_score();
772
		tempviolated = violated;
773
		remove_node(vv);
774
	      }
775
	      if ((oldscore != get_score()) || (oldviolated != violated)) {
Robert Ricci's avatar
Robert Ricci committed
776 777 778
		cerr << "Scoring problem adding a mapping - oldscore was " <<
		  oldscore <<  " newscore is " << newscore << " tempscore was "
		  << tempscore << endl;
779 780
		cerr << "oldviolated was " << oldviolated << " newviolated is "
		  << violated << " tempviolated was " << tempviolated << endl;
Robert Ricci's avatar
Robert Ricci committed
781 782
		cerr << "I was tring to map " << vn->name << " to " <<
		  newpnode->name << endl;
783 784
		print_solution();
		cerr << vinfo;
Robert Ricci's avatar
Robert Ricci committed
785 786
		abort();
	      }
787
	    }
788
	    if (add_node(vv,newpos,false,false) != 0) {
789
	      unassigned_nodes.push(vvertex_int_pair(vv,random()));
790 791
	      continue;
	    }
792 793
	  } else {
#ifdef SMART_UNMAP
794
	    unassigned_nodes.push(vvertex_int_pair(vv,random()));
795
#endif
796 797 798
	    if (freednode) {
	      continue;
	    }
799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826
	  }
#ifndef SMART_UNMAP
	}
#endif

      newscore = get_score();
      assert(newscore >= 0);

      // Negative means bad
      scorediff = bestscore - newscore;
      // This looks funny, because < 0 means worse, which means an increase in
      // score
      if (scorediff < 0) {
	nincreases++;
	avgincrease = avgincrease * (nincreases -1) / nincreases +
	  (-scorediff)  / nincreases;
      } else {
	ndecreases++;
      }
      
      bool accepttrans = false;
      if (newscore < optimal) {
	  accepttrans = true;
	  RDEBUG(cout << "accept: optimal (" << newscore << "," << optimal
		  << ")" << endl;)
      } else if (melting) {
	  accepttrans = true;
	  RDEBUG(cout << "accept: melting" << endl;)
827
      } else {
828 829 830 831 832 833 834 835 836 837 838 839
#ifdef NO_VIOLATIONS
	  if (newscore < bestscore) {
	      accepttrans = true;
	      RDEBUG(cout << "accept: better (" << newscore << "," << bestscore
		      << ")" << endl;)
	  } else if (accept(scorediff,temp)) {
	      accepttrans = true;
	      RDEBUG(cout << "accept: metropolis (" << newscore << ","
		      << bestscore << "," << expf(scorediff/(temp*sensitivity))
		      << ")" << endl;)
	  }
#else
840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856
#ifdef SPECIAL_VIOLATION_TREATMENT
	  /*
	   * In this ifdef, we always accept new solutions that have fewer
	   * violations than the old solution, and when we're trying to
	   * determine whether or not to accept a new solution with a higher
	   * score, we don't take violations into the account.
	   *
	   * The problem with this shows up at low temperatures. What can often
	   * happen is that we accept a solution with worse violations but a
	   * better (or similar) score. Then, if we were to try, say the first
	   * solution (or a score-equivalent one) again, we'd accept it again.
	   *
	   * What this leads to is 'thrashing', where we have a whole lot of
	   * variation of scores over time, but are not making any real
	   * progress. This prevents the cooling schedule from converging for
	   * much, much longer than it should really take.
	   */
857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873
          if ((violated == bestviolated) && (newscore < bestscore)) {
	      accepttrans = true;
	      RDEBUG(cout << "accept: better (" << newscore << "," << bestscore
		      << ")" << endl;)
	  } else if (violated < bestviolated) {
	      accepttrans = true;
	      RDEBUG(cout << "accept: better (violations) (" << newscore << ","
		      << bestscore << "," << violated << "," << bestviolated
		      << ")" << endl;
	          cout << "Violations: (new) " << violated << endl;
		  cout << vinfo;)
	  } else if (accept(scorediff,temp)) {
	      accepttrans = true;
	      RDEBUG(cout << "accept: metropolis (" << newscore << ","
		      << bestscore << "," << expf(scorediff/(temp*sensitivity))
		      << ")" << endl;)
	  }
874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898
#else // no SPECIAL_VIOLATION_TREATMENT
	  /*
	   * In this branch of the ifdef, we give violations no special
	   * treatment when it comes to accepting new solution - we just add
	   * them into the score. This makes assign behave in a more 'classic'
	   * simulated annealing manner.
	   *
	   * One consequence, though, is that we have to be more careful with
	   * scores. We do not want to be able to get into a situation where
	   * adding a violation results in a _lower_ score than a solution with
	   * fewer violations.
	   */
          double adjusted_new_score = newscore + violated * VIOLATION_SCORE;
	  double adjusted_old_score = bestscore + bestviolated *
	      VIOLATION_SCORE;

	  if (adjusted_new_score < adjusted_old_score) {
	    accepttrans = true;
	  } else if (accept(adjusted_old_score - adjusted_new_score,temp)) {
	    accepttrans = true;
	  }

#endif // SPECIAL_VIOLATION_TREATMENT

      }
899 900 901 902 903
#endif

      if (accepttrans) {
	bestscore = newscore;
	bestviolated = violated;
904

905 906 907 908 909
#ifdef GNUPLOT_OUTPUT
	fprintf(tempout,"%f\n",temp);
	fprintf(scoresout,"%f\n",newscore);
	fprintf(deltaout,"%f\n",-scorediff);
#endif
910

911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953
	avgscore += newscore;

	accepts++;

#ifdef CHILL
	 if (!melting) {
	     scores[accepts] = newscore;
	 }
#endif

#ifdef NO_VIOLATIONS
	if (newscore < absbest) {
#else
	if ((violated < absbestviolated) ||
	    ((violated == absbestviolated) &&
	     (newscore < absbest))) {
#endif
#ifdef SCORE_DEBUG
	  cerr << "New best solution." << endl;
#endif
	  tie(vit,veit) = vertices(VG);
	  for (;vit!=veit;++vit) {
	    absassignment[*vit] = get(vvertex_pmap,*vit)->assignment;
	    absassigned[*vit] = get(vvertex_pmap,*vit)->assigned;
	    abstypes[*vit] = get(vvertex_pmap,*vit)->type;
	  }
	  absbest = newscore;
	  absbestviolated = violated;
	  iters_to_best = iters;
#ifdef SCORE_DEBUG
	  cerr << "New best recorded" << endl;
#endif
	}
	if (newscore < optimal) {
	  cout << "OPTIMAL ( " << optimal << ")" << endl;
	  goto DONE;
	}
	// Accept change
      } else {
	// Reject change
	RDEBUG(cout << "removing: rejected change" << endl;)
	remove_node(vv);
	if (oldassigned) {
954
	  add_node(vv,oldpos,false,false);
955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053
	}
      }

      if (melting) {
	temp = avgincrease /
	  log(nincreases/ (nincreases * X0 - ndecreases * (1 - X0)));
	if (!(temp > 0.0)) {
	    temp = 0.0;
	}
      }
#ifdef TIME_TERMINATE
      if (timelimit && ((used_time() - timestart) > timelimit)) {
	printf("Reached end of run time, finishing\n");
	forcerevert = true;
	finished = true;
	goto NOTQUITEDONE;
      }
#endif

    }

#ifdef RANDOM_ASSIGNMENT
      if (violated == 0) {
	  finished = true;
      }
#endif

#ifdef REALLY_RANDOM_ASSIGNMENT
      if (unassigned_nodes.size() == 0) {
	  finished = true;
      }
#endif

NOTQUITEDONE:
      RDEBUG(printf("avgscore: %f = %f / %i\n",avgscore / (accepts +1),avgscore,accepts+1);)
      avgscore = avgscore / (accepts +1);

    if (melting) {
      melting = false;
      initialavg = avgscore;
      meltedtemp = temp;
      RDEBUG(cout << "Melting finished with a temperature of " << temp
	<< " avg score was " << initialavg << endl;)
      if (!(meltedtemp > 0.0)) { // This backwards expression to catch NaNs
	cout << "Finished annealing while melting!" << endl;
	finished = true;
	forcerevert = true;
      }
#ifdef TIME_TARGET
      if (timetarget) {
	double melttime = used_time() - meltstart;
	double timeleft = timetarget - melttime;
	double stepsleft = timeleft / melttime;
	cout << "Melting took " << melttime << " seconds, will try for "
	  << stepsleft << " temperature steps" << endl;
	temp_rate = pow(temp_stop/temp,1/stepsleft);
	cout << "Timelimit: " << timelimit << " Timeleft: " << timeleft
	  << " temp_rate: " << temp_rate << endl;
      }
#endif
    } else {
#ifdef CHILL
      if (!melting) {
	  stddev = 0;
	  for (int i = 0; i <= accepts; i++) {
	    stddev += pow(scores[i] - avgscore,2);
	  }
	  stddev /= (accepts +1);
	  stddev = sqrt(stddev);
	  temp = temp / (1 + (temp * log(1 + delta))/(3  * stddev));
      }
#else
      temp *= temp_rate;
#endif
    }


#ifdef DEBUG_TSTEP
#ifdef EPSILON_TERMINATE
#ifdef CHILL
    RDEBUG(printf("temp_end: %f %f %f\n",temp,temp * avgscore / initialavg,stddev);)
#else
    RDEBUG(printf("temp_end: %f %f\n",temp,temp * avgscore / initialavg);)
#endif
#else
    printf("temp_end: %f ",temp);
    if (trans >= mintrans) {
	if (accepts >= naccepts) {
	    printf("both");
	} else {
	    printf("trans %f",accepts*1.0/naccepts);
	}
    } else {
	printf("accepts %f",trans*1.0/mintrans);
    }
    printf("\n");
#endif
#endif
    
1054 1055 1056
    RDEBUG(
    printf("temp_end: temp: %f ratio: %f stddev: %f\n",temp,temp * avgscore / initialavg,stddev);
    );
1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086

    // Add this to the history, and computed a smoothed average
    smoothedavg = avgscore / (nhist + 1);
    for (int j = 0; j < nhist; j++) {
      smoothedavg += avghist[(hstart + j) % MAX_AVG_HIST] / (nhist + 1);
    }

    avghist[(hstart + nhist) % MAX_AVG_HIST] = avgscore;
    if (nhist < MAX_AVG_HIST) {
      nhist++;
    } else {
      hstart = (hstart +1) % MAX_AVG_HIST;
    }

#ifdef LOCAL_DERIVATIVE
    deltaavg = lastsmoothed - smoothedavg;
    deltatemp = lasttemp - temp;
#else
    deltaavg = initialavg - smoothedavg;
    deltatemp = meltedtemp - temp;
#endif

    lastsmoothed = smoothedavg;
    lasttemp = temp;

#ifdef EPSILON_TERMINATE
    RDEBUG(
       printf("avgs: real: %f, smoothed %f, initial: %f\n",avgscore,smoothedavg,initialavg);
       printf("epsilon: (%f) %f / %f * %f / %f < %f (%f)\n", fabs(deltaavg), temp, initialavg,
	   deltaavg, deltatemp, epsilon,(temp / initialavg) * (deltaavg/ deltatemp));
1087
    );
1088 1089
    if ((tsteps >= mintsteps) &&
#ifdef ALLOW_NEGATIVE_DELTA
1090 1091 1092
	((temp < 0) || isnan(temp) ||
//	 || (fabs((temp / initialavg) * (deltaavg/ deltatemp)) < epsilon))) {
	 ((temp / initialavg) * (deltaavg/ deltatemp)) < epsilon)) {
1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136
#else
	(deltaavg > 0) && ((temp / initialavg) * (deltaavg/ deltatemp) < epsilon)) {
#endif
#ifdef FINISH_HILLCLIMB
        if (!finishedonce && ((absbestviolated <= violated) && (absbest < bestscore))) {
	    // We don't actually stop, we just go do a hill-climb (basically) at the best
	    // one we previously found
	    finishedonce = true;
	    printf("Epsilon Terminated, but going back to a better solution\n");
	} else {
	    finished = true;
	}
#else
	finished = true;
#endif
	forcerevert = true;
    }
#endif

    bool revert = false;
    if (forcerevert) {
	cout << "Reverting: forced" << endl;
	revert = true;
    }

#ifndef NO_REVERT
    if (REVERT_VIOLATIONS && (absbestviolated < violated)) {
	cout << "Reverting: REVERT_VIOLATIONS" << endl;
	revert = true;
    }
    if (absbest < bestscore) {
	cout << "Reverting: best score" << endl;
	revert = true;
    }
#endif

    if (REVERT_LAST && (temp < temp_stop)) {
	cout << "Reverting: REVERT_LAST" << endl;
	revert = true;
    }

    // Only revert if the best configuration has better violations
    vvertex_list lan_nodes;
    vvertex_iterator vvertex_it,end_vvertex_it;
1137
    if (revert) {
1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150
      cout << "Reverting to best solution\n";
      // Do a full revert
      tie(vvertex_it,end_vvertex_it) = vertices(VG);
      for (;vvertex_it!=end_vvertex_it;++vvertex_it) {
	tb_vnode *vnode = get(vvertex_pmap,*vvertex_it);
	if (vnode->fixed) continue;
	if (vnode->assigned) {
	  RDEBUG(cout << "removing: revert " << vnode->name << endl;)
	  remove_node(*vvertex_it);
	} else {
	  RDEBUG(cout << "not removing: revert " << vnode->name << endl;)
	}
      }
1151 1152 1153

      // Check to make sure that our 'clean' solution scores the same as
      // the initial score - if not, that indicates a bug
1154
      if (!compare_scores(get_score(),initial_score)) {
1155
	  cout << "*** WARNING: 'Clean' score does not match initial score" <<
1156 1157 1158
	      endl << "     This indicates a bug - contact the operators" <<
	      endl << "     (initial score: " << initial_score <<
	      ", current score: " << get_score() << ")" << endl;
1159 1160 1161 1162 1163
	  // One source of this can be pclasses that are still used - check for
	  // those
	  pclass_list::iterator pit = pclasses.begin();
	  for (;pit != pclasses.end();pit++) {
	      if ((*pit)->used_members != 0) {
1164
		  cout << (*pit)->name << " is " << (*pit)->used_members
1165 1166 1167
		      << "% used" << endl;
	      }
	  }
1168
      }
1169 1170 1171 1172 1173
      tie(vvertex_it,end_vvertex_it) = vertices(VG);
      for (;vvertex_it!=end_vvertex_it;++vvertex_it) {
	tb_vnode *vnode = get(vvertex_pmap,*vvertex_it);
	if (vnode->fixed) continue;
	if (absassigned[*vvertex_it]) {
1174 1175
	  if (vnode->vclass != NULL) {
	    vnode->type = abstypes[*vvertex_it];
1176
	  }
1177
	  assert(!add_node(*vvertex_it,absassignment[*vvertex_it],true,false));
1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190
	}
      }
    }

    tsteps++;

    if (finished) {
      goto DONE;
    }
  }
 DONE:
  cout << "Done" << endl;
}