[CentOS] Yum - which repo did a package come from

> 
> Yes, I have found this is a limitation of yum. It would be nice if the
> information about the source repository could be stored somewhere.
> 
> If these were installed after the initial OS installation, and you haven't
> done a yum clean, you might be able to glean some info from the cache:
> # ls -l /var/cache/yum/*/packages
> 
> This won't give you any information about packages installed using rpm
> directly instead of yum.
> 

tony, i did yum clean when i upgraded to 5.3