SAN Perfomance - IOPS

[RobD]

Hi All,

 

I've been doing some research on the performance of SANS but if I'm honest I still don't totally understand the IOPS concept. I appreciate if a the IOPS are hight then the disks are busy but what I'm struggling to understand is what constitutes too high?

 

We essentially have two sets of storage, a HP P4300 SAS cluster and a P4300 Sata cluster which are both connected via a 1GB fibre.

The average IOPS total on the SAS is 77.4:

 

The average IOPS total on the SATA is 76.4:

 

I guess what I'm asking is when should I worried i.e. when they reach what sort of peak?

 

Thanks

[glennda]

What scale is that on?

 

77 iops is nothing... I've got a client of 60 users who have 1000 IOPS.

 

what is high IOPs really depends on what the hardware underneath will perform too.

 

What do you have running on the sans?

Edited November 5, 2013 by glennda

[RobD]

Hi,

 

Thanks for the reply, the scale goes up to 100 which I'm guessing is IOPS:

 

I'm running 3 VM hosts and basic file sharing etc. Nothing drastic really, what prompted this was we have a class of people who use VB to create projects and when they save the project (around 5 folders and 50 small files), VB freezes where as if they save locally VB doesnt freeze.

 

So I thought I'd just rule out the SAN.

[glennda]

Hi,

 

Thanks for the reply, the scale goes up to 100 which I'm guessing is IOPS:

[ATTACH=CONFIG]21346[/ATTACH]

 

I'm running 3 VM hosts and basic file sharing etc. Nothing drastic really, what prompted this was we have a class of people who use VB to create projects and when they save the project (around 5 folders and 50 small files), VB freezes where as if they save locally VB doesnt freeze.

 

So I thought I'd just rule out the SAN.

 

By the looks of it those support up to around 2000 IOPS (roughly).

 

By the sounds of that I would be looking at Anti-Virus on the server which they are saving too.

[RobD]

Cool, so I take it if the SAN reached 2000 IOPS then it would really struggle or at least be under a very heavy load?

[glennda]

Cool, so I take it if the SAN reached 2000 IOPS then it would really struggle or at least be under a very heavy load?

 

Yes - You can do testing with IOMeter- How to measure IOPS on ESX / ESXi using Iometer - Gatt IT Limited

 

This will let you actually simulate the servers being under high load.

[RobD]

Brilliant, thanks I'll take a look.