history: remove records without attached blobs during gc

Signed-off-by: CrazyMax <1951866+crazy-max@users.noreply.github.com>

solver/llbsolver/history.go

@@ -283,7 +283,9 @@ func (h *HistoryQueue) migrateBlobV2(ctx context.Context, id string, detectSkipL
 }
 
 func (h *HistoryQueue) gc() error {
+	ctx := context.Background()
 	var records []*controlapi.BuildHistoryRecord
+	var orphanRecords []*controlapi.BuildHistoryRecord
 
 	if err := h.opt.DB.View(func(tx *bolt.Tx) error {
 		b := tx.Bucket([]byte(recordsBucket))
@@ -298,13 +300,28 @@ func (h *HistoryQueue) gc() error {
 			if br.Pinned {
 				return nil
 			}
-			records = append(records, &br)
+			recs, err := h.hLeaseManager.ListResources(ctx, leases.Lease{ID: h.leaseID(string(key))})
+			if (err != nil && cerrdefs.IsNotFound(err)) || len(recs) == 0 {
+				orphanRecords = append(orphanRecords, &br)
+			} else {
+				records = append(records, &br)
+			}
 			return nil
 		})
 	}); err != nil {
 		return err
 	}
 
+	h.mu.Lock()
+	defer h.mu.Unlock()
+
+	// delete records that don't have any blobs associated with them
+	for _, r := range orphanRecords {
+		if err := h.delete(r.Ref, false); err != nil {
+			return err
+		}
+	}
+
 	// in order for record to get deleted by gc it exceed both maxentries and maxage criteria
 	if len(records) < int(h.opt.CleanConfig.MaxEntries) {
 		return nil
@@ -315,9 +332,6 @@ func (h *HistoryQueue) gc() error {
 		return records[i].CompletedAt.AsTime().After(records[j].CompletedAt.AsTime())
 	})
 
-	h.mu.Lock()
-	defer h.mu.Unlock()
-
 	now := time.Now()
 	for _, r := range records[h.opt.CleanConfig.MaxEntries:] {
 		if now.Add(-h.opt.CleanConfig.MaxAge.Duration).After(r.CompletedAt.AsTime()) {