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3 replies Latest Post - ‏2013-02-02T12:06:57Z by SystemAdmin
SystemAdmin
SystemAdmin
4779 Posts
ACCEPTED ANSWER

Pinned topic Disk Pool IOPS

‏2013-01-30T22:50:20Z |
Hi Guys,

Looking for some guidance regarding sizing a DS3500 with the dynamic disk pooling and what affect this has on IOPS. The documentation seems to suggest its using a RAID 6 'under the hood' so does this mean it would still suffer the RAID 6 IOPS write penalty (i.e. number of write IOPS x 6) or do the same rules not apply to disk pools?

Thanks
Updated on 2013-02-02T12:06:57Z at 2013-02-02T12:06:57Z by SystemAdmin
  • SystemAdmin
    SystemAdmin
    4779 Posts
    ACCEPTED ANSWER

    Re: Disk Pool IOPS

    ‏2013-01-31T11:33:14Z  in response to SystemAdmin
    DDP is a king of RAID6 and should suffer of all it "diseases". The thing which helps, RAID6 is implemented in ASIC hardware, so it's performance is near RAID5. When RAID6 was just implemented in DS series storages, there was a document which compared RAID5 and RAID6 performance. As far i remember, RAID6 performance was near to RAID5.
    Related to DDP performance compared to RAID6:
    DELL document related PowerVault MD3 (the same as DS3500)
    http://i.dell.com/sites/doccontent/shared-content/data-sheets/en/Documents/Dynamic_Disk_Pooling_Technical_Report.pdf
    I don't remember where i find this document, which compare DDP and RAID6 on DS3500 and DCS3700
    https://docs.google.com/file/d/0B2UULgVZiiXSRThidjltZEFWQW8/edit
    and, if you are interested in general performance questions, i recommend "A practical Introduction to
    Disk Storage System Performance" by Gero Schmidt
    http://www.scribd.com/doc/95013690/A-Practical-Introduction-to-Storage-Disk-Subsystem-Performance-V1-55
    and "Getting The Hang Of IOPS, An Introduction to Disk Performance"
    http://www.symantec.com/connect/articles/getting-hang-iops-v13