Redundant Array of Independent Disks (RAID) is now the mostefficient way to solve the bottleneck problem between CPU and storagedevices. In RAID 5, for the write operation, disk array controller firstreads the old data from the disks which the new data will write into andthe old parity information. Then, it calculates the new parityinformation using the old data, the new data and the old parityinformation to get the new parity. At last, disk array controller writesthe new data and the new parity information altogether into thecorresponding disks in the array. Thus, in order to write the new datainto the disk array, it should perform the two extra read operations andone extra write operation compared with RAID 0. Hence, improving thestripe write operation is the key factor in improving the writeperformance of RAID 5. The basic idea is the reduce the striperead/write operations to as few as possible. This paper discusses thedifferent situations of stripe write operation in RAID 5, and proposesan adaptive control algorithm to improve the partial stripe writeperformance. The basic idea is to reduce the stripe read/write operationas much as possible
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