Use multi-inserts for pg_enum

This allows to insert at once all the enum values defined with a given
type into pg_enum, reducing the WAL produced by roughly 10%~.  pg_enum's
indexes are opened and closed now once rather than N times.  The number
of items to insert is known in advance, making this change
straight-forward, and would happen on a CREATE TYPE .. AS ENUM.

The amount of data inserted is capped at 64kB for each insert batch.
This is similar to commits 63110c6 and e3931d01, that worked on
different catalogs.

Reported-by: Ranier Vilela
Author: Michael Paquier
Reviewed-by: Kyotaro Horiguchi, Ranier Vilela
Discussion: https://postgr.es/m/Y3M5bovrkTQbAO4W@paquier.xyz
This commit is contained in:
Michael Paquier 2022-11-16 12:41:29 +09:00
parent 09a72188cd
commit 1ff4161218
1 changed files with 42 additions and 13 deletions

View File

@ -61,14 +61,14 @@ void
EnumValuesCreate(Oid enumTypeOid, List *vals)
{
Relation pg_enum;
NameData enumlabel;
Oid *oids;
int elemno,
num_elems;
Datum values[Natts_pg_enum];
bool nulls[Natts_pg_enum];
ListCell *lc;
HeapTuple tup;
int slotCount = 0;
int nslots;
CatalogIndexState indstate;
TupleTableSlot **slot;
num_elems = list_length(vals);
@ -111,12 +111,21 @@ EnumValuesCreate(Oid enumTypeOid, List *vals)
qsort(oids, num_elems, sizeof(Oid), oid_cmp);
/* and make the entries */
memset(nulls, false, sizeof(nulls));
indstate = CatalogOpenIndexes(pg_enum);
/* allocate the slots to use and initialize them */
nslots = Min(num_elems,
MAX_CATALOG_MULTI_INSERT_BYTES / sizeof(FormData_pg_enum));
slot = palloc(sizeof(TupleTableSlot *) * nslots);
for (int i = 0; i < nslots; i++)
slot[i] = MakeSingleTupleTableSlot(RelationGetDescr(pg_enum),
&TTSOpsHeapTuple);
elemno = 0;
foreach(lc, vals)
{
char *lab = strVal(lfirst(lc));
Name enumlabel = palloc0(NAMEDATALEN);
/*
* labels are stored in a name field, for easier syscache lookup, so
@ -129,22 +138,42 @@ EnumValuesCreate(Oid enumTypeOid, List *vals)
errdetail("Labels must be %d bytes or less.",
NAMEDATALEN - 1)));
values[Anum_pg_enum_oid - 1] = ObjectIdGetDatum(oids[elemno]);
values[Anum_pg_enum_enumtypid - 1] = ObjectIdGetDatum(enumTypeOid);
values[Anum_pg_enum_enumsortorder - 1] = Float4GetDatum(elemno + 1);
namestrcpy(&enumlabel, lab);
values[Anum_pg_enum_enumlabel - 1] = NameGetDatum(&enumlabel);
ExecClearTuple(slot[slotCount]);
tup = heap_form_tuple(RelationGetDescr(pg_enum), values, nulls);
memset(slot[slotCount]->tts_isnull, false,
slot[slotCount]->tts_tupleDescriptor->natts * sizeof(bool));
CatalogTupleInsert(pg_enum, tup);
heap_freetuple(tup);
slot[slotCount]->tts_values[Anum_pg_enum_oid - 1] = ObjectIdGetDatum(oids[elemno]);
slot[slotCount]->tts_values[Anum_pg_enum_enumtypid - 1] = ObjectIdGetDatum(enumTypeOid);
slot[slotCount]->tts_values[Anum_pg_enum_enumsortorder - 1] = Float4GetDatum(elemno + 1);
namestrcpy(enumlabel, lab);
slot[slotCount]->tts_values[Anum_pg_enum_enumlabel - 1] = NameGetDatum(enumlabel);
ExecStoreVirtualTuple(slot[slotCount]);
slotCount++;
/* if slots are full, insert a batch of tuples */
if (slotCount == nslots)
{
CatalogTuplesMultiInsertWithInfo(pg_enum, slot, slotCount,
indstate);
slotCount = 0;
}
elemno++;
}
/* Insert any tuples left in the buffer */
if (slotCount > 0)
CatalogTuplesMultiInsertWithInfo(pg_enum, slot, slotCount,
indstate);
/* clean up */
pfree(oids);
for (int i = 0; i < nslots; i++)
ExecDropSingleTupleTableSlot(slot[i]);
CatalogCloseIndexes(indstate);
table_close(pg_enum, RowExclusiveLock);
}