By default, the vSphere vCenter
deployment contains a virtual appliance where the VMware management and
orchestration platform, vCenter, resides and runs from.
The default performance metric statistics collection interval within vCenter is to start rolling up data in an aggregation method starting at just one hour. Much of the data necessary for troubleshooting of performance challenges reported either same day or on the previously day is lost from the vCenter data and forces the administrator to revert to cumbersome and/or time-consuming tooling, such as vRealize Operations Manager. DBAs might not have access to such tools. Hopefully by now they have read-only access to vCenter!
The vCenter performance
statistics collection and rollup settings can be customized to provide a longer
window of time for critical metrics to be available to the administrator for
The default statistics level within vCenter is one, and is set per collection interval of days, weeks, months, then years. A default value of one eliminates or reduces the granularity of retention of critical data into the embedded PostgreSQL vCenter database.
The recommended settings are 4, 4, 3, 2, for each interval duration, as depicted here from the Heraflux labs vSphere web client. Doing so achieves a much more granular and longer retention of these critical performance metrics.
Ensure that enough free space exists on the vCenter appliance database partitions to accommodate the additional data. The consumption calculator on the same vCenter screen will help you estimate the space required. VMware has a knowledge base article on how to resize the appropriate virtual disks and partitions, available at: https://kb.vmware.com/s/article/2126276.