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sqlio results local disk vs netapp

Just to test, I ran SQLIO

on a windows 2008 box (DL785) local disk (4x300G, RAID 10)  vs a Netapp aggregate of 56 disks. Filer is running 7.2.6.1, this is a FC LUN.  Aggregate is not really that loaded.

Surprisingly to me, the results show the C drive to be faster.  I know there are various ways to tweak SQLIO but I still find this odd.  Any suggestions would be appreciated:

SQLIO: 1 thread reading for 30 secs using 2KB IOs over 128KB stripes with 64 IOs per run:

Local C:\     [sqlio -dC]

IOs/sec:  5844.79
MBs/sec:    11.41

Netapp F:\    [sqlio -dF]

IOs/sec: 2547.88
MBs/sec:     4.97

SQLIO: 1 thread writing for 30 secs using 2KB IOs over 128KB stripes with 64 IOs per run:

Local C:\    [sqlio -kW -dC]

IOs/sec: 10116.73
MBs/sec:    19.75

Netapp F:\    [sqlio -kW -dF]

IOs/sec:  1895.42
MBs/sec:     3.70

Re: sqlio results local disk vs netapp

Have you check for partition alignment, LUN type mismatch, FC frame errors, other user-level errors?

This discrepancy is shocking and can only be some unoptimized settings.

Re: sqlio results local disk vs netapp

What type of disk is the 56 disk aggregate, its RG size?  What is you measure of "not really that loaded" ?  Are disk queue lengths and latency response high in perfmon?  Do you have performance advisor on this aggregate? Are storage latencies high?

Re: sqlio results local disk vs netapp

Aggregate is a 56 disk aggregate, with standard 16 disk raid groups, total aggregate iops in DFM never exceeds 500-1000.  I have to look at all of the other stuff

Suresh

Re: sqlio results local disk vs netapp

What speed of disk?

Re: sqlio results local disk vs netapp

What HBA(s) are you using? How about drivers? Thanks,  -Wei

Re: sqlio results local disk vs netapp

These are Emulex HBA's, with Netapp Host utilities, Snapdrive 6 and MPIO.  Disks on the filer are 15k rpm

Re: sqlio results local disk vs netapp

Can you provide the Emulex HBA model #? Also, what driver are you using? Version #? How about driver parameter, such as queue depth?

Thanks,

Wei

Re: sqlio results local disk vs netapp

Has your problem been solved? I think we have Thread Link : 13413. Can you share your thoughts?

Re: sqlio results local disk vs netapp

We had an issue like this at the back end of 2009.  It was caused by a 'rogue' HBA driver that windows had download from the server vender.  Replaced with the NetApp drive and issue resolved.

Hope it helps

Bren