8 hdd Raid 10 vs. 2*(4HDD Raid 10)

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8 hdd Raid 10 vs. 2*(4HDD Raid 10)

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Hello,

     I have 8 SAS disks free in a MD1000 connected with a PERC 6/E 512Mb.

     This disks will be to fill with 16 .vhd.

     The question is, do a Big Raid 10 with the 8 disks and put all the 16 vhd's inside or do 2 raid 10 of 4 disks, and put 8 vhd in one raid and 8 in the other.

     Thanks.

Verified Answer
  • Check out the benchmarks for  4 vs 8 drives R10, (5E is the neweat adapter tested), 8 will give a considerable speed increase, hope you have a hotspare on the unit. 

    http://tweakers.net/benchdb/suite/13

     

  • There are benchmarks for (4) and (8) member r10s at the site, I was looking at the "storage" benchmarks.

    "As far as I can see Raid 10 with as much drives as possible is the better option." Roughly a 33% increase in speed with 4 disks added, dependent upon disk manufacturer's technology/drive speed.

    You can NOT add disks to a configured R10 array, your best option, if the present config is difficult to rebuild/restore data, is to clone the present array to an IDE/SATA drive, then reverse clone to the new array, or create an image. then restore. Personally I clone to another drive if possible, testing  that it fully boots , as I have seen images go south.

All Replies
  • Check out the benchmarks for  4 vs 8 drives R10, (5E is the neweat adapter tested), 8 will give a considerable speed increase, hope you have a hotspare on the unit. 

    http://tweakers.net/benchdb/suite/13

     

  • Hello,

        Thanks for the link. Please remember that the question was 2* raid 10 of  4hhd    versus   1* raid 10 of 8 hdd.

        As far as I can see Raid 10 with as much drives as possible is the better option.

        I have try to add 4 disks more to the existing raid10 of 4hdd but I don't find the option and I don't know if it's possible to add disk to existing raid 10 or you have to delete and make a new array.

                   Thanks.

  • There are benchmarks for (4) and (8) member r10s at the site, I was looking at the "storage" benchmarks.

    "As far as I can see Raid 10 with as much drives as possible is the better option." Roughly a 33% increase in speed with 4 disks added, dependent upon disk manufacturer's technology/drive speed.

    You can NOT add disks to a configured R10 array, your best option, if the present config is difficult to rebuild/restore data, is to clone the present array to an IDE/SATA drive, then reverse clone to the new array, or create an image. then restore. Personally I clone to another drive if possible, testing  that it fully boots , as I have seen images go south.