Hi Sumit,
To answer you query;
1> RAID-DP is proprietary to NETAPP RAID implementation and hence there is no way we can use the same in Hitachi storage array.
2> Hitachi Storage Array uses only the standard RAID implementation which includes RAID-6 as well but not RAID-DP.
3> In case of RAID-6 we have dual parity which is distributed over all the drives but for RAID-DP we have dual DEDICATED parity. Now this has both advantages and disadvantages. Advantage of having RAID-DP over RAID-6 is growing the RAID set for RAID-DP is very easy as one has to just add new drives and the parity will be written in the dedicate drive only. Where as for RAID-6 it means redistributing stripes throughout all the drives along with the diagonal parity calculation. In terms of performance, RAID-DP is having dedicated parity disks and hence those can become bottleneck/hotspot where as with RAID-6 we have distributed parity and hence no such bottleneck issue.
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Chayan Sarkar
Hardware Test Engineer - Senior
Hitachi Vantara
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Original Message:
Sent: 11-09-2022 08:32
From: Sumit Keshri
Subject: Benefit of RAID 6 (6D+2P) over RAID-DP (6D+2P), in terms of performance point of view.
Hi All,
Hope you are doing well.
Can anyone let me know what is the benefit of RAID 6 (6D+2P) over RAID-DP (6D+2P), in terms of performance point of view?
Why do we use RAID 6 (6D+2P) not RAID-DP(6D+2P) in the Hitachi Storage array?
Thanks in advance.
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Sumit Keshri
Senior Test Engineer
Hitachi Vantara
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