Rightsize with VMware vRealize Operations
Updated: Apr 27
In our previous blog we discussed Workload Optimization using VMware vRealize Operations (vROps). Another key vROps capability is Rightsizing, the process of resizing your VMs such that they have the vCPU and Memory they need to perform as expected. The Rightsize section can be found under Optimize Performance, the first of the four vROps pillars.
Select Rightsize and you will be presented with a list of Datacenters. Select one and you will be presented with a summary of Oversized and Undersized VMs in that Datacenter, and a list of VMs.
The Oversized VMs summary shows several things:
- Total number of VMs in that Datacenter that are oversized
- Total number of vCPU vROps is recommending for reduction and its % of total allocated
- Total amount of Memory vROps is recommending for reduction and its % of total allocated
It's important to note that vROps won't recommend anything over 50% reduction for vCPU and Memory. That is, if you have a 8 vCPU and 32GB RAM VM that vROps has determined to be oversized, the max reduction will be to 4 vCPU and 16GB RAM. vROps will iterate on this and recommend changes as necessary in the future.
The Undersized VMs summary shows several items as well:
- Total number of VMs in the Datacenter that are undersized
- Total number of vCPU vROps is recommending for increase and its % of total already allocated
- Total amount of Memory vROps is recommending for increase and its % of total already allocated
Note that vROps won't recommend anything more than 100% increase for vCPU or Memory. That is, if you have a 8 vCPU and 32GB RAM VM that vROps has determined to be undersized, the max increase recommendation will be to 16 vCPU And 64GB RAM.
The bottom widget shows a list of Clusters and the VMs in them: one tab for Oversized VMs and another for Undersized VMs. As you expand each Cluster you'll be given more details on each VM.
As you select VMs, the three options at the top are presented: RESIZE VM(S), EXCLUDE VM(S), and EXPORT ALL. Let's explore RESIZE VM(S). I've selected several VMs and clicked the RESIZE VM(S) button:
The recommendations are presented, the user can adjust the sizes with the pencil icon, click the orange box at the bottom, then select RESIZE VM(S). As stated, this will resize the VMs, which in some cases will require the restart of VMs. If vCPU and Memory Hot Add have been configured for the affected VMs, reboots won't be required. Note: reboots are always required when removing vCPU or Memory.
If you'd like to exclude certain VMs, select them and click the EXCLUDE VM(S) box. This will exclude the VM, its resources, and cost savings from reclamation considerations.
If you'd like a list, selected the VMs then click the EXPORT ALL button which will generate and download a .csv file for your review.
VMware vROps Rightsizing documentation can be found here: https://docs.vmware.com/en/vRealize-Operations-Manager/8.0/com.vmware.vcom.core.doc/GUID-871D6B56-52AE-49C2-9B64-B36BE2BE8F4F.html