Skip to content
/ server Public

MDEV-38721: refactor hierarchical read traversal into helper #4774

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Draft
luvjeetk wants to merge 1 commit into
base: main
Choose a base branch
from
+17 −12
Draft

MDEV-38721: refactor hierarchical read traversal into helper #4774

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
29 changes: 17 additions & 12 deletions sql/vector_mhnsw.cc
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1404,6 +1404,21 @@ static int search_layer(MHNSW_param *p, const FVector *target, float threshold,
return 0;
}

/*
Read-path hierarchical traversal:
descend upper layers with ef=1, then search layer 0 with requested limit.
*/
static int search_hierarchical_read(MHNSW_param *p, const FVector *target,
uint limit, Neighborhood *candidates)
{
for (; p->layer > 0; p->layer--)
{
if (int err= search_layer(p, target, NEAREST, 1, candidates, false))
return err;
}
return search_layer(p, target, NEAREST, limit, candidates, false);
}


int mhnsw_insert(TABLE *table, KEY *keyinfo)
{
Expand Down Expand Up @@ -1566,18 +1581,8 @@ int mhnsw_read_first(TABLE *table, KEY *keyinfo, Item *dist, ulonglong limit)
return err;

MHNSW_param p(ctx, graph, candidates.links[0]->max_layer);

for (; p.layer > 0; p.layer--)
{
if (int err= search_layer(&p, target, NEAREST, 1, &candidates, false))
{
graph->file->ha_rnd_end();
return err;
}
}

if (int err= search_layer(&p, target, NEAREST, static_cast<uint>(limit),
&candidates, false))
if (int err= search_hierarchical_read(&p, target, static_cast<uint>(limit),
&candidates))
{
graph->file->ha_rnd_end();
return err;
Expand Down