Active Bolck Layout:一种高性能磁盘布局机制

1.引言随着计算机技术的发展,CPU的运算速度越来越快,但磁盘存储系统速度的提高却远远跟不上CPU速度的提高。这种差别导致在许多计算机系统中,存储系统成为系统性能的瓶颈。磁盘的存储容量和存取速度的发展是不平衡的。磁盘存储容量以每年一倍的速度发展,而磁盘的存取时间仅仅每年

Active Block Layout: A High Performance Block Layout Mechanism

The access frequency of different files in file system is dissimilar. If file system can optimize the block layout of these hot files which are frequently accessed,the performance of file system will be improved. This paper presents a high performance block layout mechanism: Active Block Layout (ABL). ABL can record the access frequency of every file in file system and actively optimize the block layout of these hot files by block duplicating. The duplicated blocks can be placed in the special zone of track,which is called "Cooling Zone". ABL can automatically determine the placing position and the copy count of the blocks which need to be duplicated. In order to reduce the overhead of block duplication,this paper also presents a mechanism which uses the potential disk bandwidth to realize the block duplication,and does not obviously degrade the performance of file system.