Different Kinds of Demand

[81darrenteo]

Hi,

I am using vCOps Manager 5.6. In the Planning > Virtual Machine Capacity Usage view, I can see CPU and memory demand, effective demand and usage.

I get it that usage is the actual consumption (in memory case, the active memory) and demand is what the vm will want. But what is effective demand?

In the Planning > Host Machine Capacity Usage view, what is limited demand then?

I have combed through the documentations but couldn't find any answers. Can anyone shed some light? Thanks!

[admin]

Hi,

Limited Demand takes into account cpu/memory overhead of the VM.

Will get the details on Effective demand.

[81darrenteo]

Thanks Hugo for your response. Look forward to the details on effective demand.

[ChaseHansen]

Any update on this?

Is there any way to get VCOps to calculate say memory capacity based off Host usage and not Effective Demand?

Seems to give us the Memory Capacity/Remaining VM count based off IF the VM's are right-sized or Effective Demand and not based off the average size of our deployed VM's.

I could be totally wrong on all of this, is there any documentation?

[admin]

Hi,

Sorry..been on PTO.

I do have an answer but I need to get more information.

To answer you on the diff:

Limited Demand looks at the VM limits also. Thus if you have 2Gb memory and 500mb limit...we will use the 500mb limit value in the calcs. If no limits then we use the raw data.

Effective demand is the same as Limited until you enable "Stress". No we will look at the max values of the data colelcted.

And this is where I suppose the questions will come in.

I am busy getting more informantion but for now this is the basic answer.

[ChaseHansen]

This helps, wish there was an option to just take into account what RAM sizes we are setting.

Thanks Hugo

[admin]

U are refering to an Allocation type model....Thus taking into account what the allocated memory is.

I believe that we are looking at giving this option also.

[ChaseHansen]

Yes because for us we don't want to ever really over allocate memory and we know our VM's aren't necessarily right-sized. So if the remaining memory capacity took this into account and gave us an available capacity based off what it knows about our style of machines it would make it much more useful.

[admin]

Just so that I am clear on this.

Allocation means that if you have configured a VM with 2Gb memory we will take into account the FULL 2Gb + VM memory overhead for our capacity calulations.

Is this what your need is ?

[ChaseHansen]

Correct, much like when you are in the vSphere Thick Client and you click on a cluster, then under vSphere DRS click on View Resource Distribution Chart.

This chart is displaying the actual allocation.

I think within vCOps now we can set a % as a buffer so I think we are good there.