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IOmeter parameters

yb_benjamin
4,037 Views

Hi everybody ! 

 

I'm trying to use IOmeter to test a new AFF220 metrocluster. 

However, i don't really know which parameters to use to test it... 

 

How many workers should i use ? 

I don't really know what is Tranfert Request Size, Align I/Os if you have any ideas ? 

 

I did a try with 4K 100% random on a windows VM with 10 workers. Display results are showing  36K IOPS, however, on the LUN where resides the VM, can't go over 2000 IOPS.. Don't get that ! 

 

Thanks !

 

 

 

4 REPLIES 4

AlexDawson
3,931 Views

Hi there!

 

Synthetic IOPS Testing is not.. a great measure of anything. Have a view of this video for a bit of a discussion about why - https://www.youtube.com/watch?v=Gfg1pNMCqUQ

 

Are you concerned by the performance of your system? or rather, what brings you to want to test?

yb_benjamin
3,913 Views

Hello, 

 

Thanks for your answer.

 

I just wanted to guarantee that the metrocluster supports for example 30K IOPs. However, we don't have that much VMs on it so wanted to use a tool to "stress" the metrocluster to see how it goes. 

 

Thanks

AlexDawson
3,885 Views

Here we come to the problem of IO speed tests.

 

As you say, you have run one test which shows 36,000 IOPS, therefore, it can do 30,000+ IOPS.

 

What is the difference between the networking, connection etc of that test and the one which shows 4,000 IOPS?

yb_benjamin
3,863 Views

Hello, 

 

Yes i can see 36K IOPs from the IOmeter application. 

However, when i had a look on the LUN where we simulated IOPs, i can't go over 2K IOPs. 

Wanted to understand what could explain this difference... I tried to had a look as well on the volume or aggregate and same problem. 

 

Regards ;

 

 

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