An Energy Efficient Storage System For Astronomical Data

The explosive growth of data is leading to the rapid increase of the requirements of data storage, which makes the energy consumption of the storage system more serious. After years of research, some general-purpose energy saving technologies are widely used. But In some practical application scenarios especially astronomical observation presented in this paper, general-purpose energy saving technologies of storage system are not applicable. It faces problem of data which cannot be used timely and energy consumption of the storage system, which makes customizing the specific application scenarios of energy storage methods more important.This paper analyzes the energy saving principle of disk storage system and introduces energy management of disk, cache replacement algorithms of disk storage system and energy saving technologies of disk storage system. Meanwhile, this paper analyzes difficulties of Antarctic storage system and the existing hardware foundation, and presents an energy saving storage system which support observation mode and scientific analysis mode.The storage system is based on multilevel caching strategy with SSD, or MCS-SSD. Astronomical data are usually used according to the temporal and spatial requirements. To boost the data disks' performance, MCS-SSD further clusters correlated files and places them on the data disk via a temporal and spatial manner. MCS-SSD designs the prefetching and caching techniques to create larger disk idle time intervals. According to the load of the system, this paper presents three access models(light load, normal load, over load) to adapt to the system.At the end of this paper, a simulation experiment is being conducted. As for the existing simulators cannot adapt to the astronomical observation mode, it presents a new simulator. The experiments compare MCS-SSD and MAID in different load situations. The storage system can be extended to PB-level in the future, so it presents a PB-level architecture and conduct PB-level experiment. The results show that in the application scenario of astronomical observation MCS-SSD brings a good energy saving effect.