Association for Computing Machinery
Because of high volumes and unpredictable arrival rates, stream processing systems are not always able to keep up with input data streams - resulting in buffer overflow and uncontrolled loss of data. Load shedding and spilling are two core techniques proposed to solve this overflow problem. While load shedding simply discards data, load spilling temporarily pushes the data to disk for later reuse. Note that shedding and spilling applied to XML stream processing bring new challenges due to complex nested nature of XML structures.