@Override
        public int sizeInBytes() {
            try {
                ensureAllLoaded();
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
            return sizeInBytes;
        }
Return the largest timestamp of the messages after a given offset

@param startOffset The starting offset.
@return The largest timestamp of the messages after the given position.
core/src/main/scala/kafka/log/streamaspect/ElasticLogFileRecords.java