The top 10 PowerCLI scripts for vSphere administrators
Continuing on the resource pool theme, we now move on to a more complicated issue. If you have ever tried to maintain a production, and test and development resource pool side by side, then you most likely understand the Resource Pool Pie Paradox. In its simplest form, the paradox occurs when you have a lot of VMs sharing a big chunk of shares and a small number of VMs sharing a small chunk. When you get too far off-balance, your test and development VMs could end up getting a larger share than your production VMs during contention.
The answer to this is custom shares, but the calculations required are just too much for one person to do manually. Thankfully, Duncan Epping of VMware has shared a PowerShell script, written by Andrew Mitchell, which helps us with those calculations and determines exactly what those custom resource pool share values should be. Epping recommends scheduling the script to run weekly to make the necessary adjustments.