Upgrade

I mentioned earlier that I intended to upgrade to PG7.2.2.
I went to the website, and discovered there are rpms only for RH7.3
So I had to upgrade my server as well, from RH7.1 to 7.3
It worked like a charm, and now I have PG7.2.1-5 installed.
Is there a difference between 7.2.1 and 7.2.2 in terms of performance?
PG7.2.2 release notes mention vulnerabilities.
If it is worth the effort, can someone please direct me to the document that
presents how to upgrade from rpms? I'm sure I read something like that about
one year ago (or at least there were a couple of paragraphs within the
"Install from rpm" guide).
Thank you all.
Mihai Gheorghiu