Hi
I just have upgraded to vCOPS 5.7.1 and it looks like there are heaps of modifications in the Capacity planning area.
Previously we had a huge number of capacity remaining that did not make sense. Now with the new policies (and my experimenting) I have nothing left 🙂
I hope VMware Press releases a vCOPS bible soon that explains everything in detail
In the mean time I was hoping if someone can clarify one and other for me.
In this example I am looking at a cluster which is provisioned with 134 Ghz of CPU. The usable capacity of my profile specifies to use HA so I have a capacity of 112 Ghz.
When I look under the details of my planning > capacity > virtual machine capacity I see the following
-Over by 21 VM
-Capacity 112 Ghz
-Usage 39%
-Host usage 39%
-Effective demand 108%
-Overcommited Allocation 108%
-Host Overcommited allocation 108%
If I go to operations > details > Workload, I see the following for this cluster
-Demand 49,943 Mhz
-Usage 45,940 Mhz
-Configured 134,405 Mhz
So at this stage I am thinking that based on demand there should be enough CPU capacity left. In my policy > Capacity and Time remaining I have enabled by demand and not allocation.
When I disable "Use Stress to account for spikes and peaks" I see a dramatic change . My effective demand goes to 51% and I have capacity for another 268 VM.
Now I don't feel comfortable with this number either and I realize that this is all affected by the "underuse and stress" setting. At this stage it is set to having a demand above 50% (CPU and RAM) for 10% of every 4 hour period.
Looking at some of my hosts in the cluster, they do go over this demand setting. When I adjust the demand to 70% and check "use stress to account for spikes and peaks" I get a remainder of 60 VM. This is probably still too much
Can someone shed some light on all of this? I really want to find a sweet spot that fits my environment.
What would be a good number to use for demand when it comes to stress? The production policy that comes with vcops is set to 40%. Would that not be a bit low?
Please consider marking my answer as "helpful" or "correct"
