We are testing out different RAID configurations and I am trying to understand why we saw similar sequential read/write numbers when we had the array configured as 3 separate linear disks vs one large OBR10 with 3 volumes carved out.  

I expected to see significantly higher throughput off the single array (while testing one drive at a time).

Dell EMC ME4024 SAN with 14 x 1TB SSD

 

3 separate linear disks:

• Sequential Read (Q= 32,T= 1) : 3640 MB/s
• Sequential Write (Q= 32,T= 1) : 1887 MB/s

one large OBR10 with 3 volumes carved out:

• Sequential Read (Q= 32,T= 1) : 3646 MB/s
• Sequential Write (Q= 32,T= 1) : 1808 MB/s

 

Should we expect to see much higher IO on the large array?  Does anyone have any suggestions on what we might check?

 

Any help or suggestions would be appreciated.

 

Note: This is for a SQL Server install and we are looking at more than just sequential reads/writes.  I just wanted to simplify the problem for the forums.

 

Thanks