liuyu/pgvector
1
0
Fork 0
mirror of https://github.com/pgvector/pgvector.git synced 2026-06-29 17:21:16 +08:00
Code Issues Packages Projects Releases Wiki Activity

Improved performance

Browse Source
This commit is contained in:
Andrew Kane
2023-07-22 09:33:32 -07:00
parent f0760eee76
commit d902e1daff
1 changed files with 29 additions and 37 deletions
Download Patch File Download Diff File Expand all files Collapse all files

66
src/hnswutils.c
View File

@@ -612,42 +612,20 @@ GetCandidateDistance(HnswCandidate * hc, Datum q, FmgrInfo *procinfo, Oid collat
}
/*
* Check if a candidate is a list member by pointer
* Add to visited
*/
static bool
HnswListMemberByPointer(List *v, HnswCandidate * e)
static inline void
AddToVisited(HTAB *v, HnswCandidate * hc, Relation index, bool *found)
{
ListCell *lc2;
foreach(lc2, v)
if (index == NULL)
hash_search(v, &hc->element, HASH_ENTER, found);
else
{
HnswCandidate *v2 = (HnswCandidate *) lfirst(lc2);
ItemPointerData indextid;
if (v2->element == e->element)
return true;
ItemPointerSet(&indextid, hc->element->blkno, hc->element->offno);
hash_search(v, &indextid, HASH_ENTER, found);
}
return false;
}
/*
* Check if a candidate is a list member by block and offset
*/
static bool
HnswListMemberByBlock(List *v, HnswCandidate * e)
{
ListCell *lc2;
foreach(lc2, v)
{
HnswCandidate *v2 = (HnswCandidate *) lfirst(lc2);
/* Neighbor page not set yet */
if (v2->element->blkno == e->element->blkno && v2->element->offno == e->element->offno)
return true;
}
return false;
}
/*
@@ -659,17 +637,34 @@ SearchLayer(Datum q, List *ep, int ef, int lc, Relation index, FmgrInfo *procinf
ListCell *lc2;
List *w = NIL;
List *v = NIL;
pairingheap *C = pairingheap_allocate(CompareNearestCandidates, NULL);
pairingheap *W = pairingheap_allocate(CompareFurthestCandidates, NULL);
int wlen = 0;
HASHCTL hash_ctl;
HTAB *v;
/* Create hash table */
if (index == NULL)
{
hash_ctl.keysize = sizeof(HnswElement *);
hash_ctl.entrysize = sizeof(HnswElement *);
}
else
{
hash_ctl.keysize = sizeof(ItemPointerData);
hash_ctl.entrysize = sizeof(ItemPointerData);
}
hash_ctl.hcxt = CurrentMemoryContext;
v = hash_create("hnsw visited", 256, &hash_ctl, HASH_ELEM | HASH_BLOBS | HASH_CONTEXT);
/* Add entry points to v, C, and W */
foreach(lc2, ep)
{
HnswCandidate *hc = (HnswCandidate *) lfirst(lc2);
v = lappend(v, hc);
AddToVisited(v, hc, index, NULL);
pairingheap_add(C, &(CreatePairingHeapNode(hc)->ph_node));
pairingheap_add(W, &(CreatePairingHeapNode(hc)->ph_node));
@@ -696,15 +691,12 @@ SearchLayer(Datum q, List *ep, int ef, int lc, Relation index, FmgrInfo *procinf
HnswCandidate *e = &neighborhood->items[i];
bool visited;
/* TODO Use hash for v? */
visited = index == NULL ? HnswListMemberByPointer(v, e) : HnswListMemberByBlock(v, e);
AddToVisited(v, e, index, &visited);
if (!visited)
{
float eDistance;
v = lappend(v, e);
f = ((HnswPairingHeapNode *) pairingheap_first(W))->inner;
if (index == NULL)