Cleanup your DB before the upgrade is not a “must” but this is a good moment.
Do you also have some concerns before updating your vCenter? For sure we all have a Plan and a Plan B, Plan C …, but there is always someting you didn’t considered or expected. I would like to show you my Upgrade from 5.5 U3b to 6.0 U2.
I just want to know how much space does your vCenter DB consume and what are your biggest tables?