diff --git a/lib/persistentqueue/persistentqueue.go b/lib/persistentqueue/persistentqueue.go
index 7af7933ce..3bbb9c519 100644
--- a/lib/persistentqueue/persistentqueue.go
+++ b/lib/persistentqueue/persistentqueue.go
@@ -113,6 +113,9 @@ func (q *queue) mustResetFiles() {
 
 // GetPendingBytes returns the number of pending bytes in the queue.
 func (q *queue) GetPendingBytes() uint64 {
+	if q.readerOffset > q.writerOffset {
+		logger.Panicf("BUG: readerOffset=%d cannot exceed writerOffset=%d", q.readerOffset, q.writerOffset)
+	}
 	n := q.writerOffset - q.readerOffset
 	return n
 }
@@ -555,6 +558,9 @@ func (q *queue) nextChunkFileForRead() error {
 	if n := q.readerOffset % q.chunkFileSize; n > 0 {
 		q.readerOffset += q.chunkFileSize - n
 	}
+	if err := q.checkReaderWriterOffsets(); err != nil {
+		return err
+	}
 	q.readerLocalOffset = 0
 	q.readerPath = q.chunkFilePath(q.readerOffset)
 	r, err := filestream.Open(q.readerPath, true)
@@ -598,6 +604,14 @@ func (q *queue) readFull(buf []byte) error {
 	}
 	q.readerLocalOffset += bufLen
 	q.readerOffset += bufLen
+	return q.checkReaderWriterOffsets()
+}
+
+func (q *queue) checkReaderWriterOffsets() error {
+	if q.readerOffset > q.writerOffset {
+		return fmt.Errorf("readerOffset=%d cannot exceed writerOffset=%d; it is likely persistent queue files were corrupted on unclean shutdown",
+			q.readerOffset, q.writerOffset)
+	}
 	return nil
 }