From 2ef59a56b5df4f2449e615af36a7245f1d8a9880 Mon Sep 17 00:00:00 2001 From: Yugo Nagata Date: Fri, 20 Dec 2019 10:09:45 +0900 Subject: [PATCH v27 3/9] Allow to prolong life span of transition tables until transaction end Originally, tuplestores of AFTER trigger's transition tables were freed for each query depth. For our IVM implementation, we would like to prolong life of the tuplestores because we have to preserve them for a whole query assuming that some base tables might be changed in some trigger functions. --- src/backend/commands/trigger.c | 83 ++++++++++++++++++++++++++++++++-- src/include/commands/trigger.h | 2 + 2 files changed, 81 insertions(+), 4 deletions(-) diff --git a/src/backend/commands/trigger.c b/src/backend/commands/trigger.c index 13cb516752..aa1da7b279 100644 --- a/src/backend/commands/trigger.c +++ b/src/backend/commands/trigger.c @@ -3730,6 +3730,10 @@ typedef struct AfterTriggerEventList * end of the list, so it is relatively easy to discard them. The event * list chunks themselves are stored in event_cxt. * + * prolonged_tuplestored is a list of transition table tuplestores whose + * life are prolonged to the end of the outmost query instead of each nested + * query. + * * query_depth is the current depth of nested AfterTriggerBeginQuery calls * (-1 when the stack is empty). * @@ -3795,6 +3799,7 @@ typedef struct AfterTriggersData SetConstraintState state; /* the active S C state */ AfterTriggerEventList events; /* deferred-event list */ MemoryContext event_cxt; /* memory context for events, if any */ + List *prolonged_tuplestores; /* list of prolonged tuplestores */ /* per-query-level data: */ AfterTriggersQueryData *query_stack; /* array of structs shown below */ @@ -3830,6 +3835,7 @@ struct AfterTriggersTableData bool closed; /* true when no longer OK to add tuples */ bool before_trig_done; /* did we already queue BS triggers? */ bool after_trig_done; /* did we already queue AS triggers? */ + bool prolonged; /* are transition tables prolonged? */ AfterTriggerEventList after_trig_events; /* if so, saved list pointer */ /* @@ -3879,6 +3885,7 @@ static void TransitionTableAddTuple(EState *estate, TupleTableSlot *original_insert_tuple, Tuplestorestate *tuplestore); static void AfterTriggerFreeQuery(AfterTriggersQueryData *qs); +static void release_or_prolong_tuplestore(Tuplestorestate *ts, bool prolonged); static SetConstraintState SetConstraintStateCreate(int numalloc); static SetConstraintState SetConstraintStateCopy(SetConstraintState state); static SetConstraintState SetConstraintStateAddItem(SetConstraintState state, @@ -4725,6 +4732,45 @@ afterTriggerInvokeEvents(AfterTriggerEventList *events, } +/* + * SetTransitionTablePreserved + * + * Prolong lifespan of transition tables corresponding specified relid and + * command type to the end of the outmost query instead of each nested query. + * This enables to use nested AFTER trigger's transition tables from outer + * query's triggers. Currently, only immediate incremental view maintenance + * uses this. + */ +void +SetTransitionTablePreserved(Oid relid, CmdType cmdType) +{ + AfterTriggersTableData *table; + AfterTriggersQueryData *qs; + bool found = false; + ListCell *lc; + + /* Check state, like AfterTriggerSaveEvent. */ + if (afterTriggers.query_depth < 0) + elog(ERROR, "SetTransitionTablePreserved() called outside of query"); + + qs = &afterTriggers.query_stack[afterTriggers.query_depth]; + + foreach(lc, qs->tables) + { + table = (AfterTriggersTableData *) lfirst(lc); + if (table->relid == relid && table->cmdType == cmdType && + table->closed) + { + table->prolonged = true; + found = true; + } + } + + if (!found) + elog(ERROR,"could not find table with OID %d and command type %d", relid, cmdType); +} + + /* * GetAfterTriggersTableData * @@ -4933,6 +4979,7 @@ AfterTriggerBeginXact(void) */ afterTriggers.firing_counter = (CommandId) 1; /* mustn't be 0 */ afterTriggers.query_depth = -1; + afterTriggers.prolonged_tuplestores = NIL; /* * Verify that there is no leftover state remaining. If these assertions @@ -5093,19 +5140,19 @@ AfterTriggerFreeQuery(AfterTriggersQueryData *qs) ts = table->old_upd_tuplestore; table->old_upd_tuplestore = NULL; if (ts) - tuplestore_end(ts); + release_or_prolong_tuplestore(ts, table->prolonged); ts = table->new_upd_tuplestore; table->new_upd_tuplestore = NULL; if (ts) - tuplestore_end(ts); + release_or_prolong_tuplestore(ts, table->prolonged); ts = table->old_del_tuplestore; table->old_del_tuplestore = NULL; if (ts) - tuplestore_end(ts); + release_or_prolong_tuplestore(ts, table->prolonged); ts = table->new_ins_tuplestore; table->new_ins_tuplestore = NULL; if (ts) - tuplestore_end(ts); + release_or_prolong_tuplestore(ts, table->prolonged); if (table->storeslot) ExecDropSingleTupleTableSlot(table->storeslot); } @@ -5117,6 +5164,34 @@ AfterTriggerFreeQuery(AfterTriggersQueryData *qs) */ qs->tables = NIL; list_free_deep(tables); + + /* Release prolonged tuplestores at the end of the outmost query */ + if (afterTriggers.query_depth == 0) + { + foreach(lc, afterTriggers.prolonged_tuplestores) + { + ts = (Tuplestorestate *) lfirst(lc); + if (ts) + tuplestore_end(ts); + } + afterTriggers.prolonged_tuplestores = NIL; + } +} + +/* + * Release the tuplestore, or append it to the prolonged tuplestores list. + */ +static void +release_or_prolong_tuplestore(Tuplestorestate *ts, bool prolonged) +{ + if (prolonged && afterTriggers.query_depth > 0) + { + MemoryContext oldcxt = MemoryContextSwitchTo(CurTransactionContext); + afterTriggers.prolonged_tuplestores = lappend(afterTriggers.prolonged_tuplestores, ts); + MemoryContextSwitchTo(oldcxt); + } + else + tuplestore_end(ts); } diff --git a/src/include/commands/trigger.h b/src/include/commands/trigger.h index 194e8d5bc1..2e9f1ac8c7 100644 --- a/src/include/commands/trigger.h +++ b/src/include/commands/trigger.h @@ -261,6 +261,8 @@ extern void AfterTriggerEndSubXact(bool isCommit); extern void AfterTriggerSetState(ConstraintsSetStmt *stmt); extern bool AfterTriggerPendingOnRel(Oid relid); +extern void SetTransitionTablePreserved(Oid relid, CmdType cmdType); + /* * in utils/adt/ri_triggers.c -- 2.17.1