Address Mapping For Shingled Magnetic Recording On Bit Patterned Media

Along with the advance of Internet technology, into the era of b ig data,the digital information present explosive growth trend,the demand for large capacity storage device is huge in the storage device of market. the conventional hard disk drives at the time of improving surface density is affected by the super paramagnetic limits, Bit patterned technology is an effective way to overcome the super paramagnetic limits, the theory of Shingled Magnetic Recording technologies is to record data by overlapping part next track on previous writing good track, just like overlapping roof tile, thus reduce the track width, greatly improving the track density. The combination of the two technologies can scale the areal density to as much as 5 to 10 times.The Shingled Magnetic Recording can several times improve the capacity of the disk, but due to the overlapping coverage track of Shingled Magnetic Recording and the write head width wider will affect adjacent track of data so the Shingled Magnetic Recording is poor in random write. To solve these problems, This paper proposes a new record of stripe and data organization,to keep track of tile the independence of the read and write operations, avoiding interference from adjacent areas; proposing a new shingled magnetic recording the disk of the hot and cold data based on the way, the area is divided into hot data area and cold area in order to realize the efficient data storage. For hot data, use the hot bands as segments of the Log-structured File System(LFS), for cold data, use the cold bands as circular logs. Design a window-based hot data identification scheme to hot data map to the hot area and cold data map to the cold area by the Shingled Magnetic Recording address mapping table. The Shingled Magnetic Recording create many invalid data block on account of he out-of-place update strategy and reduces the utilization of the disk.so design three garbage collection algorithm to release the disk space is occupied by invalid data block. Specifically, to alleviate the burden of memory, call the mapping information into the cache on-demanded so can save the space of memory that to lower the cost of the SWD. Simulation results demonstrate that this proposal can improve the performance in random writing of Shingled Magnetic Recording.