diff --git a/src/hnsw.h b/src/hnsw.h
index 878e02d..442a9ea 100644
--- a/src/hnsw.h
+++ b/src/hnsw.h
@@ -363,6 +363,7 @@ typedef struct HnswScanOpaqueData
 	List	   *discarded;
 	Datum		q;
 	int			m;
+	int64		tuples;
 	MemoryContext tmpCtx;
 
 	/* Support functions */
diff --git a/src/hnswscan.c b/src/hnswscan.c
index 000c335..287341c 100644
--- a/src/hnswscan.c
+++ b/src/hnswscan.c
@@ -131,6 +131,7 @@ hnswrescan(IndexScanDesc scan, ScanKey keys, int nkeys, ScanKey orderbys, int no
 		tidhash_reset(so->v.tids);
 	so->first = true;
 	so->discarded = NIL;
+	so->tuples = 0;
 	MemoryContextReset(so->tmpCtx);
 
 	if (keys && scan->numberOfKeys > 0)
@@ -204,15 +205,34 @@ hnswgettuple(IndexScanDesc scan, ScanDirection dir)
 			if (!hnsw_streaming)
 				break;
 
-			/*
-			 * Ensure vacuum does not mark tuples as deleted during an
-			 * iteration
-			 */
-			LockPage(scan->indexRelation, HNSW_SCAN_LOCK, ShareLock);
+			if (MemoryContextMemAllocated(so->tmpCtx, false) > (work_mem * 1024L))
+			{
+				if (list_length(so->discarded) == 0)
+				{
+					ereport(NOTICE,
+							(errmsg("iterative search exceeded work_mem after " INT64_FORMAT " tuples", so->tuples),
+							 errhint("Increase work_mem to scan more tuples.")));
 
-			HnswBench("scan iteration", so->w = ResumeScanItems(scan));
+					break;
+				}
 
-			UnlockPage(scan->indexRelation, HNSW_SCAN_LOCK, ShareLock);
+				/* Return remaining tuples and exit */
+				/* TODO sort */
+				so->w = so->discarded;
+				so->discarded = NIL;
+			}
+			else
+			{
+				/*
+				 * Ensure vacuum does not mark tuples as deleted during an
+				 * iteration
+				 */
+				LockPage(scan->indexRelation, HNSW_SCAN_LOCK, ShareLock);
+
+				HnswBench("scan iteration", so->w = ResumeScanItems(scan));
+
+				UnlockPage(scan->indexRelation, HNSW_SCAN_LOCK, ShareLock);
+			}
 
 #if defined(HNSW_MEMORY)
 			elog(INFO, "memory: %zu KB", MemoryContextMemAllocated(so->tmpCtx, false) / 1024);
@@ -240,6 +260,8 @@ hnswgettuple(IndexScanDesc scan, ScanDirection dir)
 			continue;
 		}
 
+		so->tuples++;
+
 		heaptid = &element->heaptids[--element->heaptidsLength];
 
 		MemoryContextSwitchTo(oldCtx);
diff --git a/test/t/039_hnsw_streaming.pl b/test/t/039_hnsw_streaming.pl
index 5379b56..ecb5b5e 100644
--- a/test/t/039_hnsw_streaming.pl
+++ b/test/t/039_hnsw_streaming.pl
@@ -16,15 +16,28 @@ $node->start;
 $node->safe_psql("postgres", "CREATE EXTENSION vector;");
 $node->safe_psql("postgres", "CREATE TABLE tst (i int4, v vector($dim));");
 $node->safe_psql("postgres",
-	"INSERT INTO tst SELECT i, ARRAY[$array_sql] FROM generate_series(1, 10000) i;"
+	"INSERT INTO tst SELECT i, ARRAY[$array_sql] FROM generate_series(1, 100000) i;"
 );
-$node->safe_psql("postgres", "CREATE INDEX ON tst USING hnsw (v vector_l2_ops);");
+$node->safe_psql("postgres", qq(
+	SET maintenance_work_mem = '128MB';
+	SET max_parallel_maintenance_workers = 2;
+	CREATE INDEX ON tst USING hnsw (v vector_l2_ops)
+));
 
 my $count = $node->safe_psql("postgres", qq(
 	SET enable_seqscan = off;
 	SET hnsw.streaming = on;
-	SELECT COUNT(*) FROM (SELECT v FROM tst WHERE i % 1000 = 0 ORDER BY v <-> (SELECT v FROM tst LIMIT 1) LIMIT 11) t;
+	SET work_mem = '8MB';
+	SELECT COUNT(*) FROM (SELECT v FROM tst WHERE i % 10000 = 0 ORDER BY v <-> (SELECT v FROM tst LIMIT 1) LIMIT 11) t;
 ));
 is($count, 10);
 
+my ($ret, $stdout, $stderr) = $node->psql("postgres", qq(
+	SET enable_seqscan = off;
+	SET hnsw.streaming = on;
+	SET work_mem = '2MB';
+	SELECT COUNT(*) FROM (SELECT v FROM tst WHERE i % 10000 = 0 ORDER BY v <-> (SELECT v FROM tst LIMIT 1) LIMIT 11) t;
+));
+like($stderr, qr/iterative search exceeded work_mem after \d+ tuples/);
+
 done_testing();