Clear AQO_cache_mem_ctx memory context.

Author: Alena Rybakina

aqo.c

@@ -94,6 +94,7 @@ double		log_selectivity_lower_bound = -30;
  * after a query parsing and is used during the query planning.
  */
 MemoryContext		AQOMemoryContext;
+MemoryContext		AQO_cache_mem_ctx;
 QueryContextData	query_context;
 /* Additional plan info */
 int njoins;
@@ -235,6 +236,9 @@ _PG_init(void)
 	AQOMemoryContext = AllocSetContextCreate(TopMemoryContext,
 											 "AQOMemoryContext",
 											 ALLOCSET_DEFAULT_SIZES);
+	AQO_cache_mem_ctx = AllocSetContextCreate(TopMemoryContext,
+											 "AQO_cache_mem_ctx",
+											 ALLOCSET_DEFAULT_SIZES);
 	RegisterResourceReleaseCallback(aqo_free_callback, NULL);
 	RegisterAQOPlanNodeMethods();
 }

aqo.h

@@ -252,6 +252,7 @@ extern int njoins;
 
 /* Memory context for long-live data */
 extern MemoryContext AQOMemoryContext;
+extern MemoryContext AQO_cache_mem_ctx;
 
 /* Saved hook values in case of unload */
 extern post_parse_analyze_hook_type prev_post_parse_analyze_hook;

cardinality_hooks.c

@@ -226,7 +226,7 @@ aqo_get_parameterized_baserel_size(PlannerInfo *root,
 
 	if (query_context.use_aqo || query_context.learn_aqo)
 	{
-		MemoryContext mcxt;
+		MemoryContext old_ctx_m;
 
 		selectivities = list_concat(
 							get_selectivities(root, param_clauses, rel->relid,
@@ -241,7 +241,8 @@ aqo_get_parameterized_baserel_size(PlannerInfo *root,
 		relid = planner_rt_fetch(rel->relid, root)->relid;
 		get_eclasses(allclauses, &nargs, &args_hash, &eclass_hash);
 
-		mcxt = MemoryContextSwitchTo(CacheMemoryContext);
+		old_ctx_m = MemoryContextSwitchTo(AQO_cache_mem_ctx);
+
 		forboth(l, allclauses, l2, selectivities)
 		{
 			current_hash = get_clause_hash(
@@ -251,7 +252,7 @@ aqo_get_parameterized_baserel_size(PlannerInfo *root,
 							  *((double *) lfirst(l2)));
 		}
 
-		MemoryContextSwitchTo(mcxt);
+		MemoryContextSwitchTo(old_ctx_m);
 		pfree(args_hash);
 		pfree(eclass_hash);
 	}

selectivity_cache.c

@@ -89,5 +89,6 @@ selectivity_cache_find_global_relid(int clause_hash, int global_relid)
 void
 selectivity_cache_clear(void)
 {
+	MemoryContextReset(AQO_cache_mem_ctx);
 	objects = NIL;
 }