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SQL server 2012 know issues when using Disk Spanning


#1

Hi,
I plan to implement the disk spanning feature in Windows Server 2012 in order to create a single 12 TB volume (using 2 x 6TB disks). The new volume will hold a 10TB database while using SQL Server 2012.

The question is: Are there any known performance or stability issues when using SQL Server 2012 with the Widows Server disk spanning feature?

Regards,
-r


#2

I'm not aware of an issues of that nature. Alternatively, you could define the database as 2 files, one on each disk.

Have you taken steps to ensure that tempdb and the database log file(s) are on separate, physical disks from the main database (and each other!)? that will have more of a performance impact than creating a spanned volume, I believe.


#3

Thank you for the prompt reply and for raising a great point! ...yes, in my design the main mdb file will live in the 12TB drive (spanned drive). For the log file, I plan to have a separate 12TB drive (another spanned drive) where the log file will reside..


#4

With this massive amount of data, probably running in production environment, and you want both performance and stability, in my oppinion, you must at least have

  • 2 volumes (data+log and temp)
  • set each volume up as raid 0+1 (stripe+mirror) as a minimum (preferably hardware raid)
  • have a great backup (and restore) plan

If each volume should hold 12 TB, that would require 3x6 TB disks (per volume).
If you want even better performance, other raid plans can be implemented (by the cost of more disks and probably other raid controllers).
But you should consider this: can you afford downtime if one disk fails? or more disks (you would have to consider better raid than 0+1 for this)?

I would personaly choose stability over performance, if I had to choose.

Spanning disks is a no go in production server, in my opinion, as this will get you no performance nor stability.


#5

great points, @bitsmed! Also, with a spanned drive, you have all your eggs in one basket. Stable, for sure, but a little dangerous.