diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/backend/optimizer/plan/planner.c | 51 | ||||
| -rw-r--r-- | src/backend/utils/adt/selfuncs.c | 38 | ||||
| -rw-r--r-- | src/include/utils/selfuncs.h | 3 |
3 files changed, 48 insertions, 44 deletions
diff --git a/src/backend/optimizer/plan/planner.c b/src/backend/optimizer/plan/planner.c index 1a58d733fa6..5579dfa65e4 100644 --- a/src/backend/optimizer/plan/planner.c +++ b/src/backend/optimizer/plan/planner.c @@ -148,9 +148,6 @@ static double get_number_of_groups(PlannerInfo *root, double path_rows, grouping_sets_data *gd, List *target_list); -static Size estimate_hashagg_tablesize(Path *path, - const AggClauseCosts *agg_costs, - double dNumGroups); static RelOptInfo *create_grouping_paths(PlannerInfo *root, RelOptInfo *input_rel, PathTarget *target, @@ -3660,40 +3657,6 @@ get_number_of_groups(PlannerInfo *root, } /* - * estimate_hashagg_tablesize - * estimate the number of bytes that a hash aggregate hashtable will - * require based on the agg_costs, path width and dNumGroups. - * - * XXX this may be over-estimating the size now that hashagg knows to omit - * unneeded columns from the hashtable. Also for mixed-mode grouping sets, - * grouping columns not in the hashed set are counted here even though hashagg - * won't store them. Is this a problem? - */ -static Size -estimate_hashagg_tablesize(Path *path, const AggClauseCosts *agg_costs, - double dNumGroups) -{ - Size hashentrysize; - - /* Estimate per-hash-entry space at tuple width... */ - hashentrysize = MAXALIGN(path->pathtarget->width) + - MAXALIGN(SizeofMinimalTupleHeader); - - /* plus space for pass-by-ref transition values... */ - hashentrysize += agg_costs->transitionSpace; - /* plus the per-hash-entry overhead */ - hashentrysize += hash_agg_entry_size(agg_costs->numAggs); - - /* - * Note that this disregards the effect of fill-factor and growth policy - * of the hash-table. That's probably ok, given default the default - * fill-factor is relatively high. It'd be hard to meaningfully factor in - * "double-in-size" growth policies here. - */ - return hashentrysize * dNumGroups; -} - -/* * create_grouping_paths * * Build a new upperrel containing Paths for grouping and/or aggregation. @@ -4130,7 +4093,7 @@ consider_groupingsets_paths(PlannerInfo *root, ListCell *lc; ListCell *l_start = list_head(gd->rollups); AggStrategy strat = AGG_HASHED; - Size hashsize; + double hashsize; double exclude_groups = 0.0; Assert(can_hash); @@ -4297,9 +4260,9 @@ consider_groupingsets_paths(PlannerInfo *root, /* * Account first for space needed for groups we can't sort at all. */ - availspace -= (double) estimate_hashagg_tablesize(path, - agg_costs, - gd->dNumHashGroups); + availspace -= estimate_hashagg_tablesize(path, + agg_costs, + gd->dNumHashGroups); if (availspace > 0 && list_length(gd->rollups) > 1) { @@ -6424,7 +6387,7 @@ add_paths_to_grouping_rel(PlannerInfo *root, RelOptInfo *input_rel, if (can_hash) { - Size hashaggtablesize; + double hashaggtablesize; if (parse->groupingSets) { @@ -6735,7 +6698,7 @@ create_partial_grouping_paths(PlannerInfo *root, if (can_hash && cheapest_total_path != NULL) { - Size hashaggtablesize; + double hashaggtablesize; /* Checked above */ Assert(parse->hasAggs || parse->groupClause); @@ -6768,7 +6731,7 @@ create_partial_grouping_paths(PlannerInfo *root, if (can_hash && cheapest_partial_path != NULL) { - Size hashaggtablesize; + double hashaggtablesize; hashaggtablesize = estimate_hashagg_tablesize(cheapest_partial_path, diff --git a/src/backend/utils/adt/selfuncs.c b/src/backend/utils/adt/selfuncs.c index 2e3fab6a958..e6837869cf6 100644 --- a/src/backend/utils/adt/selfuncs.c +++ b/src/backend/utils/adt/selfuncs.c @@ -113,6 +113,7 @@ #include "catalog/pg_statistic.h" #include "catalog/pg_statistic_ext.h" #include "executor/executor.h" +#include "executor/nodeAgg.h" #include "miscadmin.h" #include "nodes/makefuncs.h" #include "nodes/nodeFuncs.h" @@ -3428,6 +3429,43 @@ estimate_hash_bucket_stats(PlannerInfo *root, Node *hashkey, double nbuckets, ReleaseVariableStats(vardata); } +/* + * estimate_hashagg_tablesize + * estimate the number of bytes that a hash aggregate hashtable will + * require based on the agg_costs, path width and number of groups. + * + * We return the result as "double" to forestall any possible overflow + * problem in the multiplication by dNumGroups. + * + * XXX this may be over-estimating the size now that hashagg knows to omit + * unneeded columns from the hashtable. Also for mixed-mode grouping sets, + * grouping columns not in the hashed set are counted here even though hashagg + * won't store them. Is this a problem? + */ +double +estimate_hashagg_tablesize(Path *path, const AggClauseCosts *agg_costs, + double dNumGroups) +{ + Size hashentrysize; + + /* Estimate per-hash-entry space at tuple width... */ + hashentrysize = MAXALIGN(path->pathtarget->width) + + MAXALIGN(SizeofMinimalTupleHeader); + + /* plus space for pass-by-ref transition values... */ + hashentrysize += agg_costs->transitionSpace; + /* plus the per-hash-entry overhead */ + hashentrysize += hash_agg_entry_size(agg_costs->numAggs); + + /* + * Note that this disregards the effect of fill-factor and growth policy + * of the hash table. That's probably ok, given that the default + * fill-factor is relatively high. It'd be hard to meaningfully factor in + * "double-in-size" growth policies here. + */ + return hashentrysize * dNumGroups; +} + /*------------------------------------------------------------------------- * diff --git a/src/include/utils/selfuncs.h b/src/include/utils/selfuncs.h index 0ce2175f3e8..84805152338 100644 --- a/src/include/utils/selfuncs.h +++ b/src/include/utils/selfuncs.h @@ -186,6 +186,9 @@ extern void estimate_hash_bucket_stats(PlannerInfo *root, Node *hashkey, double nbuckets, Selectivity *mcv_freq, Selectivity *bucketsize_frac); +extern double estimate_hashagg_tablesize(Path *path, + const AggClauseCosts *agg_costs, + double dNumGroups); extern List *get_quals_from_indexclauses(List *indexclauses); extern Cost index_other_operands_eval_cost(PlannerInfo *root, |