Research On Secondary Storage Structure In Continuous System

With the advent of cloud computing and the age of big data,explosive growth make the data information of new digital information increasing at an annual rate of 30%,every big enterprise's demand of data storage becomes more and more high.Expanding the scale of the data center and the application of equipment increasing,followed the question is high energy consumption,which is not only increased the overall operating costs of data center,but also affects the reliability of the data and the stability of the system,high efficiency and energy saving storage systems' research has the vital significance.The data operation of the continuous storage system is usually write one-time,which is not rewritten after writing and seldom read,and it is not need the high speed of data transmission.In this paper,we propose an energy-saving data layout SC-RAID5(RAID System with SSD as Cache)based on SSD as a secondary Cache storage medium.The specific research contents are as follows:1)first of all,it introduced the relevant knowledge of storage technology,and several kinds of typical structure(RAID 0 ~ RAID6),appeared in the development of the RAID technology,has introduced the specific layout and the reliability analysis,then introduced the SSD's structure classification,characteristics and the key technology,which used widely in the present application fields of storage media.2)secondly,analysed the energy consumption problem of the traditional disk and the advantages of cache application,this paper proposes a new energy storage model: SC-RAID5,using the SSD as the second cache of the storage system to write the system data and the parity data,and using the Data Incremental Parity algorithm suitable for continuous data written to calculate the parity data,it effectively minimize the write punishment by "readmodify-write",and improves the system performance.After the system has been set,the data in SSD is written back to the RAID disk array.When there is no data write,the RAID disks are in standby mode,and when there is data write,the disk is scheduled to run state,this can reduce the system energy consumption.Set the appropriate data written back mechanism,the data within the SSD timely written to the disk array,and erase processing the SSD part of the write back data,then in unified recovery of storage space,those can prolong the service life of SSD,and improve the stability of the system.3)Finally,introduces the MD of the Linux kernel module related contents,based on the kernel modify MD code to implement the data layout of the SC-RAID5,through the tests under continuous load,contrast eRAID,PARAID,and SRAID5 energy-saving data layout,SC-RAID5 optimization layout in writing performance,response time and the energy of the system are improved significantly.Experiment shows that the sc-raid5 optimization structure has greatly improved the performance of continuous data storage system based on written data.which can also be used in RAID4 and RAID6.