PostgreSQL Source Code  git master
geqo_main.c File Reference
#include "postgres.h"
#include <math.h>
#include "optimizer/geqo_misc.h"
#include "optimizer/geqo_mutation.h"
#include "optimizer/geqo_pool.h"
#include "optimizer/geqo_random.h"
#include "optimizer/geqo_selection.h"
Include dependency graph for geqo_main.c:

Go to the source code of this file.

Functions

static int gimme_pool_size (int nr_rel)
 
static int gimme_number_generations (int pool_size)
 
RelOptInfogeqo (PlannerInfo *root, int number_of_rels, List *initial_rels)
 

Variables

int Geqo_effort
 
int Geqo_pool_size
 
int Geqo_generations
 
double Geqo_selection_bias
 
double Geqo_seed
 

Function Documentation

◆ geqo()

RelOptInfo* geqo ( PlannerInfo root,
int  number_of_rels,
List initial_rels 
)

Definition at line 67 of file geqo_main.c.

68 {
69  GeqoPrivateData private;
70  int generation;
71  Chromosome *momma;
72  Chromosome *daddy;
73  Chromosome *kid;
74  Pool *pool;
75  int pool_size,
76  number_generations;
77 
78 #ifdef GEQO_DEBUG
79  int status_interval;
80 #endif
81  Gene *best_tour;
82  RelOptInfo *best_rel;
83 
84 #if defined(ERX)
85  Edge *edge_table; /* list of edges */
86  int edge_failures = 0;
87 #endif
88 #if defined(CX) || defined(PX) || defined(OX1) || defined(OX2)
89  City *city_table; /* list of cities */
90 #endif
91 #if defined(CX)
92  int cycle_diffs = 0;
93  int mutations = 0;
94 #endif
95 
96 /* set up private information */
97  root->join_search_private = (void *) &private;
98  private.initial_rels = initial_rels;
99 
100 /* initialize private number generator */
101  geqo_set_seed(root, Geqo_seed);
102 
103 /* set GA parameters */
104  pool_size = gimme_pool_size(number_of_rels);
105  number_generations = gimme_number_generations(pool_size);
106 #ifdef GEQO_DEBUG
107  status_interval = 10;
108 #endif
109 
110 /* allocate genetic pool memory */
111  pool = alloc_pool(root, pool_size, number_of_rels);
112 
113 /* random initialization of the pool */
114  random_init_pool(root, pool);
115 
116 /* sort the pool according to cheapest path as fitness */
117  sort_pool(root, pool); /* we have to do it only one time, since all
118  * kids replace the worst individuals in
119  * future (-> geqo_pool.c:spread_chromo ) */
120 
121 #ifdef GEQO_DEBUG
122  elog(DEBUG1, "GEQO selected %d pool entries, best %.2f, worst %.2f",
123  pool_size,
124  pool->data[0].worth,
125  pool->data[pool_size - 1].worth);
126 #endif
127 
128 /* allocate chromosome momma and daddy memory */
129  momma = alloc_chromo(root, pool->string_length);
130  daddy = alloc_chromo(root, pool->string_length);
131 
132 #if defined (ERX)
133 #ifdef GEQO_DEBUG
134  elog(DEBUG2, "using edge recombination crossover [ERX]");
135 #endif
136 /* allocate edge table memory */
137  edge_table = alloc_edge_table(root, pool->string_length);
138 #elif defined(PMX)
139 #ifdef GEQO_DEBUG
140  elog(DEBUG2, "using partially matched crossover [PMX]");
141 #endif
142 /* allocate chromosome kid memory */
143  kid = alloc_chromo(root, pool->string_length);
144 #elif defined(CX)
145 #ifdef GEQO_DEBUG
146  elog(DEBUG2, "using cycle crossover [CX]");
147 #endif
148 /* allocate city table memory */
149  kid = alloc_chromo(root, pool->string_length);
150  city_table = alloc_city_table(root, pool->string_length);
151 #elif defined(PX)
152 #ifdef GEQO_DEBUG
153  elog(DEBUG2, "using position crossover [PX]");
154 #endif
155 /* allocate city table memory */
156  kid = alloc_chromo(root, pool->string_length);
157  city_table = alloc_city_table(root, pool->string_length);
158 #elif defined(OX1)
159 #ifdef GEQO_DEBUG
160  elog(DEBUG2, "using order crossover [OX1]");
161 #endif
162 /* allocate city table memory */
163  kid = alloc_chromo(root, pool->string_length);
164  city_table = alloc_city_table(root, pool->string_length);
165 #elif defined(OX2)
166 #ifdef GEQO_DEBUG
167  elog(DEBUG2, "using order crossover [OX2]");
168 #endif
169 /* allocate city table memory */
170  kid = alloc_chromo(root, pool->string_length);
171  city_table = alloc_city_table(root, pool->string_length);
172 #endif
173 
174 
175 /* my pain main part: */
176 /* iterative optimization */
177 
178  for (generation = 0; generation < number_generations; generation++)
179  {
180  /* SELECTION: using linear bias function */
181  geqo_selection(root, momma, daddy, pool, Geqo_selection_bias);
182 
183 #if defined (ERX)
184  /* EDGE RECOMBINATION CROSSOVER */
185  gimme_edge_table(root, momma->string, daddy->string, pool->string_length, edge_table);
186 
187  kid = momma;
188 
189  /* are there any edge failures ? */
190  edge_failures += gimme_tour(root, edge_table, kid->string, pool->string_length);
191 #elif defined(PMX)
192  /* PARTIALLY MATCHED CROSSOVER */
193  pmx(root, momma->string, daddy->string, kid->string, pool->string_length);
194 #elif defined(CX)
195  /* CYCLE CROSSOVER */
196  cycle_diffs = cx(root, momma->string, daddy->string, kid->string, pool->string_length, city_table);
197  /* mutate the child */
198  if (cycle_diffs == 0)
199  {
200  mutations++;
201  geqo_mutation(root, kid->string, pool->string_length);
202  }
203 #elif defined(PX)
204  /* POSITION CROSSOVER */
205  px(root, momma->string, daddy->string, kid->string, pool->string_length, city_table);
206 #elif defined(OX1)
207  /* ORDER CROSSOVER */
208  ox1(root, momma->string, daddy->string, kid->string, pool->string_length, city_table);
209 #elif defined(OX2)
210  /* ORDER CROSSOVER */
211  ox2(root, momma->string, daddy->string, kid->string, pool->string_length, city_table);
212 #endif
213 
214 
215  /* EVALUATE FITNESS */
216  kid->worth = geqo_eval(root, kid->string, pool->string_length);
217 
218  /* push the kid into the wilderness of life according to its worth */
219  spread_chromo(root, kid, pool);
220 
221 
222 #ifdef GEQO_DEBUG
223  if (status_interval && !(generation % status_interval))
224  print_gen(stdout, pool, generation);
225 #endif
226 
227  }
228 
229 
230 #if defined(ERX)
231 #if defined(GEQO_DEBUG)
232  if (edge_failures != 0)
233  elog(LOG, "[GEQO] failures: %d, average: %d",
234  edge_failures, (int) number_generations / edge_failures);
235  else
236  elog(LOG, "[GEQO] no edge failures detected");
237 #else
238  /* suppress variable-set-but-not-used warnings from some compilers */
239  (void) edge_failures;
240 #endif
241 #endif
242 
243 #if defined(CX) && defined(GEQO_DEBUG)
244  if (mutations != 0)
245  elog(LOG, "[GEQO] mutations: %d, generations: %d",
246  mutations, number_generations);
247  else
248  elog(LOG, "[GEQO] no mutations processed");
249 #endif
250 
251 #ifdef GEQO_DEBUG
252  print_pool(stdout, pool, 0, pool_size - 1);
253 #endif
254 
255 #ifdef GEQO_DEBUG
256  elog(DEBUG1, "GEQO best is %.2f after %d generations",
257  pool->data[0].worth, number_generations);
258 #endif
259 
260 
261  /*
262  * got the cheapest query tree processed by geqo; first element of the
263  * population indicates the best query tree
264  */
265  best_tour = (Gene *) pool->data[0].string;
266 
267  best_rel = gimme_tree(root, best_tour, pool->string_length);
268 
269  if (best_rel == NULL)
270  elog(ERROR, "geqo failed to make a valid plan");
271 
272  /* DBG: show the query plan */
273 #ifdef NOT_USED
274  print_plan(best_plan, root);
275 #endif
276 
277  /* ... free memory stuff */
278  free_chromo(root, momma);
279  free_chromo(root, daddy);
280 
281 #if defined (ERX)
282  free_edge_table(root, edge_table);
283 #elif defined(PMX)
284  free_chromo(root, kid);
285 #elif defined(CX)
286  free_chromo(root, kid);
287  free_city_table(root, city_table);
288 #elif defined(PX)
289  free_chromo(root, kid);
290  free_city_table(root, city_table);
291 #elif defined(OX1)
292  free_chromo(root, kid);
293  free_city_table(root, city_table);
294 #elif defined(OX2)
295  free_chromo(root, kid);
296  free_city_table(root, city_table);
297 #endif
298 
299  free_pool(root, pool);
300 
301  /* ... clear root pointer to our private storage */
302  root->join_search_private = NULL;
303 
304  return best_rel;
305 }
#define LOG
Definition: elog.h:25
#define DEBUG2
Definition: elog.h:23
#define DEBUG1
Definition: elog.h:24
#define ERROR
Definition: elog.h:33
float gimme_edge_table(PlannerInfo *root, Gene *tour1, Gene *tour2, int num_gene, Edge *edge_table)
Definition: geqo_erx.c:93
void free_edge_table(PlannerInfo *root, Edge *edge_table)
Definition: geqo_erx.c:74
int gimme_tour(PlannerInfo *root, Edge *edge_table, Gene *new_gene, int num_gene)
Definition: geqo_erx.c:194
Edge * alloc_edge_table(PlannerInfo *root, int num_gene)
Definition: geqo_erx.c:54
Cost geqo_eval(PlannerInfo *root, Gene *tour, int num_gene)
Definition: geqo_eval.c:57
RelOptInfo * gimme_tree(PlannerInfo *root, Gene *tour, int num_gene)
Definition: geqo_eval.c:163
int Gene
Definition: geqo_gene.h:30
double Geqo_seed
Definition: geqo_main.c:43
static int gimme_number_generations(int pool_size)
Definition: geqo_main.c:347
static int gimme_pool_size(int nr_rel)
Definition: geqo_main.c:315
double Geqo_selection_bias
Definition: geqo_main.c:42
void geqo_mutation(PlannerInfo *root, Gene *tour, int num_gene)
void sort_pool(PlannerInfo *root, Pool *pool)
Definition: geqo_pool.c:135
void free_chromo(PlannerInfo *root, Chromosome *chromo)
Definition: geqo_pool.c:176
void free_pool(PlannerInfo *root, Pool *pool)
Definition: geqo_pool.c:69
void random_init_pool(PlannerInfo *root, Pool *pool)
Definition: geqo_pool.c:91
Chromosome * alloc_chromo(PlannerInfo *root, int string_length)
Definition: geqo_pool.c:162
void spread_chromo(PlannerInfo *root, Chromosome *chromo, Pool *pool)
Definition: geqo_pool.c:187
Pool * alloc_pool(PlannerInfo *root, int pool_size, int string_length)
Definition: geqo_pool.c:42
void geqo_set_seed(PlannerInfo *root, double seed)
Definition: geqo_random.c:20
void free_city_table(PlannerInfo *root, City *city_table)
void pmx(PlannerInfo *root, Gene *tour1, Gene *tour2, Gene *offspring, int num_gene)
void ox1(PlannerInfo *root, Gene *mom, Gene *dad, Gene *offspring, int num_gene, City *city_table)
int cx(PlannerInfo *root, Gene *tour1, Gene *tour2, Gene *offspring, int num_gene, City *city_table)
void ox2(PlannerInfo *root, Gene *mom, Gene *dad, Gene *offspring, int num_gene, City *city_table)
void px(PlannerInfo *root, Gene *tour1, Gene *tour2, Gene *offspring, int num_gene, City *city_table)
City * alloc_city_table(PlannerInfo *root, int num_gene)
void geqo_selection(PlannerInfo *root, Chromosome *momma, Chromosome *daddy, Pool *pool, double bias)
Cost worth
Definition: geqo_gene.h:35
Gene * string
Definition: geqo_gene.h:34
void * join_search_private
Definition: pathnodes.h:385
Definition: geqo_gene.h:39
int string_length
Definition: geqo_gene.h:42
Chromosome * data
Definition: geqo_gene.h:40

References alloc_chromo(), alloc_city_table(), alloc_edge_table(), alloc_pool(), cx(), Pool::data, DEBUG1, DEBUG2, elog(), ERROR, free_chromo(), free_city_table(), free_edge_table(), free_pool(), geqo_eval(), geqo_mutation(), Geqo_seed, geqo_selection(), Geqo_selection_bias, geqo_set_seed(), gimme_edge_table(), gimme_number_generations(), gimme_pool_size(), gimme_tour(), gimme_tree(), PlannerInfo::join_search_private, LOG, ox1(), ox2(), pmx(), px(), random_init_pool(), sort_pool(), spread_chromo(), generate_unaccent_rules::stdout, Chromosome::string, Pool::string_length, and Chromosome::worth.

Referenced by make_rel_from_joinlist().

◆ gimme_number_generations()

static int gimme_number_generations ( int  pool_size)
static

Definition at line 347 of file geqo_main.c.

348 {
349  if (Geqo_generations > 0)
350  return Geqo_generations;
351 
352  return pool_size;
353 }
int Geqo_generations
Definition: geqo_main.c:41

References Geqo_generations.

Referenced by geqo().

◆ gimme_pool_size()

static int gimme_pool_size ( int  nr_rel)
static

Definition at line 315 of file geqo_main.c.

316 {
317  double size;
318  int minsize;
319  int maxsize;
320 
321  /* Legal pool size *must* be at least 2, so ignore attempt to select 1 */
322  if (Geqo_pool_size >= 2)
323  return Geqo_pool_size;
324 
325  size = pow(2.0, nr_rel + 1.0);
326 
327  maxsize = 50 * Geqo_effort; /* 50 to 500 individuals */
328  if (size > maxsize)
329  return maxsize;
330 
331  minsize = 10 * Geqo_effort; /* 10 to 100 individuals */
332  if (size < minsize)
333  return minsize;
334 
335  return (int) ceil(size);
336 }
int Geqo_pool_size
Definition: geqo_main.c:40
int Geqo_effort
Definition: geqo_main.c:39

References Geqo_effort, and Geqo_pool_size.

Referenced by geqo().

Variable Documentation

◆ Geqo_effort

int Geqo_effort

Definition at line 39 of file geqo_main.c.

Referenced by gimme_pool_size().

◆ Geqo_generations

int Geqo_generations

Definition at line 41 of file geqo_main.c.

Referenced by gimme_number_generations().

◆ Geqo_pool_size

int Geqo_pool_size

Definition at line 40 of file geqo_main.c.

Referenced by gimme_pool_size().

◆ Geqo_seed

double Geqo_seed

Definition at line 43 of file geqo_main.c.

Referenced by geqo().

◆ Geqo_selection_bias

double Geqo_selection_bias

Definition at line 42 of file geqo_main.c.

Referenced by geqo().