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/*
 * EMULAB-COPYRIGHT
 * Copyright (c) 2003 University of Utah and the Flux Group.
 * All rights reserved.
 */

#include "anneal.h"

/*
 * 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;
  
// Map of virtual node name to the physical node name it's fixed too.
// 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;

// 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;
  }
  r = std::random() % 1000;
  if (r < p) {
    return 1;
  }
  return 0;
}

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/*
 * This overly-verbose function returns true if it's okay to map vn to pn,
 * false otherwise
 */
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inline bool pnode_is_match(tb_vnode *vn, tb_pnode *pn) {
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  // 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) {
    if (tr->current_load >= tr->max_load) {
      // It's at or over its max load
      if (allow_overload) {
	// 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 {
	if (pn->current_type_record->current_load >=
	    pn->current_type_record->max_load) {
	  // It's at or over its max load
	  if (allow_overload) {
	    // 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;
    }
  }

  return matched;
}

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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;
  
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  tb_pnode *newpnode = NULL;
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  /*
  int enabled_pclasses = 0;
  for (int i = 0; i < num_types; i++) {
    if ((*acceptable_types)[i]->disabled) {
	continue;
    }
    enabled_pclasses++;
  }
  cout << "Looking for a pnode for " << vn->name << " - there are " <<
      enabled_pclasses << " to choose from (" << num_types << " total)" << endl;
  assert(num_types == enabled_pclasses);
  */
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  int i = std::random()%num_types;
  int first = i;
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  bool first_time_through = true;
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  for (;;) {
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    // Stopping condition - stop if we're back to the first one, and this isn't
    // our first time through the loop
    if (i == first) {
      if (first_time_through) {
	first_time_through = false;
      } else {
	// Couldn't find a sutable node
	return NULL;
      }
    }

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    i = (i+1)%num_types;
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    // Skip pclasses that have been disabled
    if ((*acceptable_types)[i]->disabled) {
	i = std::rand()%num_types;
	continue;
    }

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#ifdef PCLASS_SIZE_BALANCE
    int acceptchance = 1000 * (*acceptable_types)[i]->size * 1.0 /
	npnodes;
    if ((std::rand() % 1000) < acceptchance) {
	continue;
    }
#endif
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    // For load balancing only
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REDO_SEARCH:
    tb_pnode* firstmatch = NULL;
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#ifndef FIND_PNODE_SEARCH
    // If not searching for the pnode, just grab the front one
    newpnode = (*acceptable_types)[i]->members[vn->type]->front();
#else
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#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
    if ((*acceptable_types)[i]->members.find(vn->type) ==
	    (*acceptable_types)[i]->members.end()) {
	continue;
    }
#endif
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    list<tb_pnode*>::iterator it = (*acceptable_types)[i]->members[vn->type]->L.begin();
#ifdef LOAD_BALANCE
    int skip = std::rand() % (*acceptable_types)[i]->members[vn->type]->L.size();
    // Skip the begging of the list
    for (int j = 0; j < skip; j++) {
	it++;
    }
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#endif // LOAD_BALANCE
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    while (it != (*acceptable_types)[i]->members[vn->type]->L.end()) {
#ifdef LOAD_BALANCE
	if ((*it)->typed) {
	    if ((*it)->current_type.compare(vn->type)) {
		it++;
	    } else {
		if (firstmatch == NULL) {
		    firstmatch = *it;
		}
		double acceptchance = 1 - (*it)->current_load * 1.0
		    / (*it)->max_load;

	        int p = 1000 * acceptchance;
		if ((std::random() % 1000) < (1000 * acceptchance)) {
		    break;
		} else {
		    it++;
		}
	    }
	} else {
	    break;
	}
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#else // LOAD_BALANCE
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	if (pnode_is_match(vn,*it)) {
	    break; 
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	} else {
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	    it++;
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	}
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#endif // LOAD_BALANCE
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    }
    if (it == (*acceptable_types)[i]->members[vn->type]->L.end()) {
#ifdef LOAD_BALANCE
	if (firstmatch) {
	    //newpnode = firstmatch;
	    goto REDO_SEARCH;
	} else {
	    newpnode = NULL;
	}
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#else // LOAD_BALANCE
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	newpnode = NULL;
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#endif // LOAD_BALANCE
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    } else {
	newpnode = *it;
    }
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#endif // FIND_PNODE_SEARCH
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#ifdef PCLASS_DEBUG
    cerr << "Found pclass: " <<
      (*acceptable_types)[i]->name << " and node " <<
      (newpnode == NULL ? "NULL" : newpnode->name) << "\n";
#endif
    if (newpnode != NULL) {
      RDEBUG(cout << " to " << newpnode->name << endl;)
      return newpnode;
    }
  }
}


/* When this is finished the state will reflect the best solution found. */
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void anneal(bool scoring_selftest, double scale_neighborhood)
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{
  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;
  double temp = init_temp;
  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()) {
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      cout << "Fixed node: " << (*fixed_it).first <<
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	"does not exist." << endl;
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      exit(EXIT_UNRETRYABLE);
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    }
    vvertex vv = vname2vertex[(*fixed_it).first];
    if (pname2vertex.find((*fixed_it).second) == pname2vertex.end()) {
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      cout << "Fixed node: " << (*fixed_it).second <<
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	" not available." << endl;
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      exit(EXIT_UNRETRYABLE);
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    }
    pvertex pv = pname2vertex[(*fixed_it).second];
    tb_vnode *vn = get(vvertex_pmap,vv);
    tb_pnode *pn = get(pvertex_pmap,pv);
    if (vn->vclass != NULL) {
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      cout << "Can not have fixed nodes be in a vclass!.\n";
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      exit(EXIT_UNRETRYABLE);
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    }
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    if (add_node(vv,pv,false,false) == 1) {
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      cout << "Fixed node: Could not map " << vn->name <<
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	" to " << pn->name << endl;
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      exit(EXIT_UNRETRYABLE);
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    }
    vn->fixed = true;
    num_fixed++;
  }

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

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  /* 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();

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  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) {
      assert(vn->fixed);
      absassignment[*vit] = vn->assignment;
      abstypes[*vit] = vn->type;
    } else {
      unassigned_nodes.push(vvertex_int_pair(*vit,std::random()));
    }
  }

  int neighborsize;
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  neighborsize = (nnodes - num_fixed) * npclasses;
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  if (neighborsize < min_neighborhood_size) {
    neighborsize = min_neighborhood_size;
  }
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  // Allow scaling of the neighborhood size, so we can make assign try harder
  // (or less hard)
  neighborsize = (int)(neighborsize * scale_neighborhood);

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#ifdef CHILL
  double scores[neighborsize];
#endif

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  if (num_fixed >= nnodes) {
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    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
  melting = true;
#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

    if (melting) {
      cout << "Doing melting run" << endl;
    }

    while ((melting && (trans < melt_trans))
#ifdef NEIGHBOR_LENGTH
	    || (trans < neighborsize)) {
#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 {
	int start = std::random()%nnodes;
	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 {
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	    cout << "**** Error, unable to find any non-fixed nodes" << endl;
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	    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
      }
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      tb_pnode *newpnode = find_pnode(vn);
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#ifndef FREE_IMMEDIATELY
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      if (oldassigned) {
	RDEBUG(cout << "removing: !lan, oldassigned" << endl;)
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	  remove_node(vv);
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      }
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#endif
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      if (newpnode == NULL) {
	// We're not going to be re-assigning this one
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#ifndef SMART_UNMAP
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	unassigned_nodes.push(vvertex_int_pair(vv,std::random()));
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#endif
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	// need to free up nodes
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#ifdef SMART_UNMAP
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	// 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;
	int offi = std::rand();
	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;
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	  }
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	  foundnode = true;
	  break;
	}
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	if (foundnode) {
	  assert((*acceptable_types)[index]->used_members[vn->type]->size());
	  tb_pclass::tb_pnodeset::iterator it = (*acceptable_types)[index]->used_members[vn->type]->begin();
	  int j = std::rand() % (*acceptable_types)[index]->used_members[vn->type]->size();
	  while (j > 0) {
	    it++;
	    j--;
	  }
	  tb_vnode_set::iterator it2 = (*it)->assigned_nodes.begin();
	  int k = std::rand() % (*it)->assigned_nodes.size();
	  while (k > 0) {
	    it2++;
	    k--;
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	  }
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	  tb_vnode *kickout = *it2;
	  assert(kickout->assigned);
	  vvertex toremove = vname2vertex[kickout->name];
	  newpnode = *it;
	  remove_node(toremove);
	  unassigned_nodes.push(vvertex_int_pair(toremove,
		std::random()));
	} else {
	  cerr << "Failed to find a replacement!" << endl;
	}
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#else
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	int start = std::random()%nnodes;
	int toremove = start;
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#ifdef SMART_UNMAP

#ifdef PER_VNODE_TT
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	  tt_entry tt = vnode_type_table[vn->name];
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#else
	  tt_entry tt = type_table[vn->type];
#endif
	  pclass_vector *acceptable_types = tt.second;

	  while (1) {
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	    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) {
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		  break;
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		}
	      }
	      if (j == acceptable_types->size()) {
		keepgoing = true;
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	      }
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	    }

	    if (!keepgoing) {
	      break;
	    }

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#else
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	    while (get(vvertex_pmap,virtual_nodes[toremove])->fixed ||
		(! get(vvertex_pmap,virtual_nodes[toremove])->assigned)) {
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#endif
	      toremove = (toremove +1) % nnodes;
	      if (toremove == start) {
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		toremove = -1;
		break;
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	      }
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	    }
	    if (toremove >= 0) {
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	      RDEBUG(cout << "removing: freeing up nodes" << endl;)
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		remove_node(virtual_nodes[toremove]);
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	      unassigned_nodes.push(vvertex_int_pair(virtual_nodes[toremove],
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		    std::random()));
	    }
	    continue;
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#endif /* SMART_UNMAP */
#ifndef SMART_UNMAP
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	  } else {
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#else
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	  }
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#endif
	  if (newpnode != NULL) {
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	    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();
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	      if (!add_node(vv,newpos,false,true)) {
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		remove_node(vv);
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	      }
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	      assert(oldscore == get_score());
	    }
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	    if (add_node(vv,newpos,false,true) != 0) {
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	      unassigned_nodes.push(vvertex_int_pair(vv,std::random()));
	      continue;
	    }
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	  } else {
#ifdef SMART_UNMAP
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	    unassigned_nodes.push(vvertex_int_pair(vv,std::random()));
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#endif
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	    if (freednode) {
	      continue;
	    }
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	  }
#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;)
      } else
#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
          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;)
	  }
#endif

      if (accepttrans) {
	bestscore = newscore;
	bestviolated = violated;
#ifdef GNUPLOT_OUTPUT
	fprintf(tempout,"%f\n",temp);
	fprintf(scoresout,"%f\n",newscore);
	fprintf(deltaout,"%f\n",-scorediff);
#endif
	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) {
780
	  add_node(vv,oldpos,false,true);
781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963
	}
      }

      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
    
    // Revert to best found so far - do link/lan migration as well
#ifdef SCORE_DEBUG
    cerr << "Reverting to best known solution." << endl;
#endif


    // 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));
    )
    if ((tsteps >= mintsteps) &&
#ifdef ALLOW_NEGATIVE_DELTA
	((fabs(deltaavg) < 0.0000001)
	 || (fabs((temp / initialavg) * (deltaavg/ deltatemp)) < epsilon))) {
#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;
964
    if (revert) {
965 966 967 968 969 970 971 972 973 974 975 976 977
      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;)
	}
      }
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      // Check to make sure that our 'clean' solution scores the same as
      // the initial score - if not, that indicates a bug
981
      if (!compare_scores(get_score(),initial_score)) {
982
	  cout << "*** WARNING: 'Clean' score does not match initial score" <<
983 984 985
	      endl << "     This indicates a bug - contact the operators" <<
	      endl << "     (initial score: " << initial_score <<
	      ", current score: " << get_score() << ")" << endl;
986 987 988 989 990
	  // 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) {
991
		  cout << (*pit)->name << " is " << (*pit)->used_members
992 993 994
		      << "% used" << endl;
	      }
	  }
995
      }
996 997 998 999 1000
      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]) {
1001 1002
	  if (vnode->vclass != NULL) {
	    vnode->type = abstypes[*vvertex_it];
1003
	  }
1004
	  assert(!add_node(*vvertex_it,absassignment[*vvertex_it],true,true));
1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017
	}
      }
    }

    tsteps++;

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