Redundant Array of Independent Disks (RAID) system have been widely used in
the enterprise, especially RAID-5 system. The RAID-5 system has parity with
every stripe in each disks, it can not only recovers fail when some data crashed,
but also improves performance. In the recent years, solid-state drives (SSDs)
becomes more popular. Some of researches used SSDs as storage devices in the
RAID-5 system. However, there are some bottlenecks in the SSD-Based RAID-5
since characteristic of SSDs. When there comes updating data in the SSD-Based
RAID-5, it needs reading old-data and parity, then recalculates and generates new
parity, and writes updating data and new parity into disks. Updating parity too
frequently will decrease lifetime of SSD since NAND
ash memory has limited
endurance. It also makes worse performance. In this paper, we proposed a novel
parity bu er management strategy that we exploit two di erent parity cache as
bu er in the RAID controller to improve the additional overhead that is overmuch
parity writing by data updating in the SSD-Based RAID-5. The experiment re-
sults show that we improved the performance of the proposed strategy is increased
by 2.81% to 41.6% under di erent traces.

Redundant Array of Independent Disks (RAID) system have been widely used in
the enterprise, especially RAID-5 system. The RAID-5 system has parity with
every stripe in each disks, it can not only recovers fail when some data crashed,
but also improves performance. In the recent years, solid-state drives (SSDs)
becomes more popular. Some of researches used SSDs as storage devices in the
RAID-5 system. However, there are some bottlenecks in the SSD-Based RAID-5
since characteristic of SSDs. When there comes updating data in the SSD-Based
RAID-5, it needs reading old-data and parity, then recalculates and generates new
parity, and writes updating data and new parity into disks. Updating parity too
frequently will decrease lifetime of SSD since NAND
ash memory has limited
endurance. It also makes worse performance. In this paper, we proposed a novel
parity bu er management strategy that we exploit two di erent parity cache as
bu er in the RAID controller to improve the additional overhead that is overmuch
parity writing by data updating in the SSD-Based RAID-5. The experiment re-
sults show that we improved the performance of the proposed strategy is increased
by 2.81% to 41.6% under di erent traces.

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