add assert for sorted bitmap

dgraph/cmd/bulk/reduce.go

@@ -285,8 +285,9 @@ func (r *reducer) writeTmpSplits(ci *countIndexer, wg *sync.WaitGroup) {
 		if kvs == nil || len(kvs.Kv) == 0 {
 			continue
 		}
-		// kvs contain the split generated after rollup. Hence, the keys to be inserted to skiplist
-		// are already sorted.
+		sort.Slice(kvs.Kv, func(i, j int) bool {
+			return bytes.Compare(kvs.Kv[i].Key, kvs.Kv[j].Key) < 0
+		})
 		b := skl.NewBuilder(int64(kvs.Size()) + 1<<20)
 		for _, kv := range kvs.Kv {
 			if err := badger.ValidEntry(ci.tmpDb, kv.Key, kv.Value); err != nil {

posting/list.go

@@ -1151,6 +1151,7 @@ func (ro *rollupOutput) split(startUid uint64) error {
 	// Provide a 30% cushion, because NSplit doesn't do equal splitting based on maxListSize.
 	bms := r.Split(f, uint64(0.7*float64(maxListSize)))
 
+	var prev uint64 = 0
 	for i, bm := range bms {
 		c := bm.GetCardinality()
 		if c == 0 {
@@ -1180,6 +1181,8 @@ func (ro *rollupOutput) split(startUid uint64) error {
 		if i == 0 && startUid == 1 {
 			start = 1
 		}
+		x.AssertTruef(prev < start, "Bitmaps not sorted | prev: %d, curr: %d", prev, start)
+		prev = start
 		ro.parts[start] = newpl
 	}