Disk Configuration

[DebiJo]

I have a dual XEON processor server with 1 disk controller and 6 disks. I have no money in the budget, so I can't add anything to it. For the best possible performance, should I:

put all 6 disks in a RAID 5 array OS/Data/Logs
or
put 2 disks in a RAID 1 for OS & Program Files
put 4 disks in a RAID 5 for Data and Logs
or
something else?

I know none of my options are premier, however, I am limited to what I can work with. I don't want to loose too much disk space, as my drives are only 18 gig each. So, if I sacrifice some disk space, I need it to be worth it.

Thanks in advance,
Debi

 

[Corran007]

The answer is it depends. Doesnt it always?

Will this be a dedicated sql server? Will it be a high volume server or just moderate use. How much read performance is needed? How much write preformance? Low io hotspots? How much redunancy? does single or multiple drive faliure cause outages to sqlserver?

More information is needed really.
another option for estreme is raid-10 or raid -01 for data files, program and os on raid 1, log on raid 1(seperate from program and os. But thats proably more than you need.

Either of your options are viable. Most of my servers are raid5 all the way.

 

[miq]

hi,

RAID 0+1 is recommanded for best read/write perfomrnace
(ideal for data/log files)
RAID 1/5 is a good alternate.
(good for os/program files)

bye
miq

 

[DebiJo]

Okay. I guess what I am really asking is this. I am very limited to my disk configuration and have no money to fix it, I have only 6 disks to use for everything. Best I can figure, I only have 3 options. (2 disks in a RAID 1 leaves 4 disks for a RAID 5)

A single RAID 5 for OS, DATA and LOGS
A RAID 5 for DATA, and a RAID 1 for OS & LOGS
A RAID 5 for DATA & LOGS and a RAID 1 for OS

Which would be the best out of this selection? The databases will be mostly write. Not alot of long drawn out queries. 9 databases, from 20 meg to 5 gig in size. It is a dedicated SQL server. I'll get my best disk space spread using the single RAID 5, but I don't think that's best for performance.

Thanks,
Debi

 

[MDXer]

For performance reasons dealing with how the Raid spans the data across the drives you really should do RAID5 on odd number of disks. 3, 5, or 7.

"Shoot Me! Shoot Me NOW!!!"
- Daffy Duck

 

[NortonES2]

I would do the following:-

2 disks RAID 1 - O/S SQLServer and log files

4 disks RAID 5 + online spare - data files

-------------------------------

If it doesn't leak oil it must be empty!!