I got a response from support, the problem was resolved so i checked.
The installation lastest now 63 minutes. So there is progression, but nowhere nere the performance you should expect from the environment.
@rmokkink, I have just realized that I had received similar instructions from the support too: last Thursday, less than 3 hours after my last reprovisioning (and subsequent comment in the case, indicating that it didn't help at all), they told me that the issue had been resolved and they instructed me to re-provision again.
But after having read your feedback, I don't feel like I want to reprovision once again and re-do all the tedious group_vars and inventory edits again, probably for nothing at all in the end By the way, have you found a way to quickly perform those edits again ?
@Razique, Hi ! Any news from your colleagues by any chance ?