What would be the optimal disk config for SQL Server 2008 R2?

Question

We have a new Dell R710 server that came with the following storage configuration:

8 x 146GB SAS 10k 6Gbps disks
1 x Perc H700 Integrated Controller (2 x 4 disks - 2 ports each supporting 4 disks)

1. What would be the optimal configuration if we were just after performance?

2. What would be the optimal configuration if we were after performance but wanted data resilience.

3. As per 2 above but with a hot standby disk?

We plan to run Windows 2008 R2 and SQL Server 2008 R2.

Maximising storage capacity isn't a prime concern.

Having scanned Server Fault and other resources, my initial thoughts were:

2 x disks in RAID 1 for OS
4 x disks in RAID 10 for data files
2 x disks in RAID 1 for transaction logs

I'd also thought about putting the tempdb on either the transaction log disks or the OS disks?

Answer 1

My guess would be to:

1. For performance only: RAID 0 (this would be seen as only 1 disk having a total storage space of 1168GB;

2. For performance, but with data resilience: RAID 5+0 (Min. 6 disks required), or you could also opt for a RAID 1+0 configuration, making 4 pairs of RAID 1, and making an array of 4x2 disks in RAID 0;

                                    RAID 0
                                      ║
      ╔═════════════════╦═════════════╩═══════════╦══════════════════════╗
      ║                 ║                         ║                      ║
    RAID 1           RAID 1                    RAID 1                 RAID 1 
   (2x146GB)        (2x146GB)                 (2x146GB)              (2x146GB)
   

For a total storage space of 584GB that will be seen as one only disk because of the RAID 0 stripping feature.

In 3, if you prefer to have a hot spare disk, than RAID 0+5 could become handy.

EDIT #1

After having read your suggestion for a 2-4-2 disk configuration, I guess this wouldn't be needed. I would personally favor a RAID 1+0 configuration as above-illustrated. I don't think the gain will be that much, since you have 8 disks of the same speed. This would have been different if you would have had two disks slower than the 6 others, then I would have considered using those two for the OS. But as of the current situation, I guess the gain would be negligeable.

Furthermore, it is much negigeable if your DBAs or programmers create the right indexes for the right data within their database. Having four disks that fast stripping together, and assuring the resilience through RAID 1, I believe you won't have trouble this way.

I hope this helps! =)

Does this help?

Answer 2

I about the same config - you can find some answers here: http://serverfault.com/questions/106806/1-logical-drive-vs-2-logical-drivers-on-1-raid-controller-to-separate-data-from-l