From 9d46fec85b84db27f840e2e0a06eefd0cfcfc2ed Mon Sep 17 00:00:00 2001 From: houzj Date: Thu, 18 Feb 2021 10:35:11 +0800 Subject: [PATCH 3/4] reloption parallel_dml_enabled Add new table option parallel_dml_enabled. In addition to the GUC option, the user may want a mechanism for specifying parallel dml with finer granularity, to specify the use of parallel dml for specific tables. The new table option parallel_dml_enabled allows this. The default is true. --- src/backend/access/common/reloptions.c | 25 +++++++++++++++++++------ src/backend/optimizer/util/clauses.c | 18 +++++++++++++++++- src/bin/psql/tab-complete.c | 1 + src/include/utils/rel.h | 23 +++++++++++++++++++++++ 4 files changed, 60 insertions(+), 7 deletions(-) diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c index c687d3e..938131a 100644 --- a/src/backend/access/common/reloptions.c +++ b/src/backend/access/common/reloptions.c @@ -168,6 +168,15 @@ static relopt_bool boolRelOpts[] = }, true }, + { + { + "parallel_dml_enabled", + "Enables \"parallel dml\" feature for this table", + RELOPT_KIND_HEAP | RELOPT_KIND_PARTITIONED, + ShareUpdateExclusiveLock + }, + true + }, /* list terminator */ {{NULL}} }; @@ -1859,7 +1868,9 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind) {"vacuum_index_cleanup", RELOPT_TYPE_BOOL, offsetof(StdRdOptions, vacuum_index_cleanup)}, {"vacuum_truncate", RELOPT_TYPE_BOOL, - offsetof(StdRdOptions, vacuum_truncate)} + offsetof(StdRdOptions, vacuum_truncate)}, + {"parallel_dml_enabled", RELOPT_TYPE_BOOL, + offsetof(StdRdOptions, parallel_dml_enabled)} }; return (bytea *) build_reloptions(reloptions, validate, kind, @@ -1961,13 +1972,15 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate) bytea * partitioned_table_reloptions(Datum reloptions, bool validate) { - /* - * There are no options for partitioned tables yet, but this is able to do - * some validation. - */ + static const relopt_parse_elt tab[] = { + {"parallel_dml_enabled", RELOPT_TYPE_BOOL, + offsetof(PartitionedOptions, parallel_dml_enabled)} + }; + return (bytea *) build_reloptions(reloptions, validate, RELOPT_KIND_PARTITIONED, - 0, NULL, 0); + sizeof(PartitionedOptions), + tab, lengthof(tab)); } /* diff --git a/src/backend/optimizer/util/clauses.c b/src/backend/optimizer/util/clauses.c index eb6eee5..f134681 100644 --- a/src/backend/optimizer/util/clauses.c +++ b/src/backend/optimizer/util/clauses.c @@ -1222,6 +1222,7 @@ target_rel_max_parallel_hazard_recurse(Relation rel, * 1) enable_parallel_dml is off * 2) INSERT...ON CONFLICT...DO UPDATE * 3) INSERT without SELECT + * 4) the reloption parallel_dml_enabled is set to off * * (Note: we don't do in-depth parallel-safety checks here, we do only the * cheaper tests that can quickly exclude obvious cases for which @@ -1232,8 +1233,10 @@ bool is_parallel_possible_for_modify(Query *parse) { bool hasSubQuery; + bool parallel_enabled; RangeTblEntry *rte; ListCell *lc; + Relation rel; Assert(IsModifySupportedInParallelMode(parse->commandType)); @@ -1271,7 +1274,20 @@ is_parallel_possible_for_modify(Query *parse) if (!hasSubQuery) return false; - return true; + /* + * Check if parallel_dml_enabled is enabled for the target table, + * if not, skip the safety checks. + * + * (Note: if the target table is partitioned, the parallel_dml_enabled + * option setting of the partitions are ignored). + */ + rte = rt_fetch(parse->resultRelation, parse->rtable); + rel = table_open(rte->relid, NoLock); + + parallel_enabled = RelationGetParallelDML(rel, true); + table_close(rel, NoLock); + + return parallel_enabled; } /***************************************************************************** diff --git a/src/bin/psql/tab-complete.c b/src/bin/psql/tab-complete.c index b64db82..ee7f48c 100644 --- a/src/bin/psql/tab-complete.c +++ b/src/bin/psql/tab-complete.c @@ -1110,6 +1110,7 @@ static const char *const table_storage_parameters[] = { "autovacuum_vacuum_threshold", "fillfactor", "log_autovacuum_min_duration", + "parallel_dml_enabled", "parallel_workers", "toast.autovacuum_enabled", "toast.autovacuum_freeze_max_age", diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h index 2a41a00..1197ae2 100644 --- a/src/include/utils/rel.h +++ b/src/include/utils/rel.h @@ -307,6 +307,7 @@ typedef struct StdRdOptions int parallel_workers; /* max number of parallel workers */ bool vacuum_index_cleanup; /* enables index vacuuming and cleanup */ bool vacuum_truncate; /* enables vacuum to truncate a relation */ + bool parallel_dml_enabled; /* enables planner's use of parallel DML */ } StdRdOptions; #define HEAP_MIN_FILLFACTOR 10 @@ -425,6 +426,28 @@ typedef struct ViewOptions VIEW_OPTION_CHECK_OPTION_CASCADED) /* + * PartitionedOptions + * Contents of rd_options for partitioned tables + */ +typedef struct PartitionedOptions +{ + int32 vl_len_; /* varlena header (do not touch directly!) */ + bool parallel_dml_enabled; /* enables planner's use of parallel DML */ +} PartitionedOptions; + +/* + * RelationGetParallelDML + * Returns the relation's parallel_dml_enabled reloption setting. + * Note multiple eval of argument! + */ +#define RelationGetParallelDML(relation, defaultpd) \ + ((relation)->rd_options ? \ + (relation->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ? \ + ((PartitionedOptions *) (relation)->rd_options)->parallel_dml_enabled :\ + ((StdRdOptions *) (relation)->rd_options)->parallel_dml_enabled) : \ + (defaultpd)) + +/* * RelationIsValid * True iff relation descriptor is valid. */ -- 2.7.2.windows.1