database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-11-13 16:22:44 +03:00
Code Activity

Avoid copying index tuples when building an index.

Browse Source 
The previous code, perhaps out of concern for avoid memory leaks, formed
the tuple in one memory context and then copied it to another memory
context.  However, this doesn't appear to be necessary, since
index_form_tuple and the functions it calls take precautions against
leaking memory.  In my testing, building the tuple directly inside the
sort context shaves several percent off the index build time.
Rearrange things so we do that.

Patch by me.  Review by Amit Kapila, Tom Lane, Andres Freund.
This commit is contained in:
Robert Haas
2014-07-01 10:34:42 -04:00
parent 03a25cec8d
commit 9f03ca9151
9 changed files with 44 additions and 45 deletions
Download Patch File Download Diff File Expand all files Collapse all files

32
src/backend/access/hash/hash.c
View File

@@ -142,26 +142,23 @@ hashbuildCallback(Relation index,
HashBuildState *buildstate = (HashBuildState *) state;
IndexTuple itup;
/* form an index tuple and point it at the heap tuple */
itup = _hash_form_tuple(index, values, isnull);
itup->t_tid = htup->t_self;
/* Hash indexes don't index nulls, see notes in hashinsert */
if (IndexTupleHasNulls(itup))
{
pfree(itup);
if (isnull[0])
return;
}
/* Either spool the tuple for sorting, or just put it into the index */
if (buildstate->spool)
_h_spool(itup, buildstate->spool);
_h_spool(buildstate->spool, &htup->t_self, values, isnull);
else
{
/* form an index tuple and point it at the heap tuple */
itup = _hash_form_tuple(index, values, isnull);
itup->t_tid = htup->t_self;
_hash_doinsert(index, itup);
pfree(itup);
}
buildstate->indtuples += 1;
pfree(itup);
}
/*
@@ -184,10 +181,6 @@ hashinsert(PG_FUNCTION_ARGS)
#endif
IndexTuple itup;
/* generate an index tuple */
itup = _hash_form_tuple(rel, values, isnull);
itup->t_tid = *ht_ctid;
/*
* If the single index key is null, we don't insert it into the index.
* Hash tables support scans on '='. Relational algebra says that A = B
@@ -197,11 +190,12 @@ hashinsert(PG_FUNCTION_ARGS)
* NOTNULL scans, but that's an artifact of the strategy map architecture
* chosen in 1986, not of the way nulls are handled here.
*/
if (IndexTupleHasNulls(itup))
{
pfree(itup);
if (isnull[0])
PG_RETURN_BOOL(false);
}
/* generate an index tuple */
itup = _hash_form_tuple(rel, values, isnull);
itup->t_tid = *ht_ctid;
_hash_doinsert(rel, itup);

5
src/backend/access/hash/hashsort.c
View File

@@ -90,9 +90,10 @@ _h_spooldestroy(HSpool *hspool)
* spool an index entry into the sort file.
*/
void
_h_spool(IndexTuple itup, HSpool *hspool)
_h_spool(HSpool *hspool, ItemPointer self, Datum *values, bool *isnull)
{
tuplesort_putindextuple(hspool->sortstate, itup);
tuplesort_putindextuplevalues(hspool->sortstate, hspool->index,
self, values, isnull);
}
/*