Hi,

I used to have exactly the same problem when the machine rebooted in the middle of an RPM installation or if the rpm process was killed -9.

On Jan 9, 2008 7:41 PM, Kai Schaetzl < maillists@conactive.com> wrote:
The process doesn't die, but doesn't seem to do anything
from that point on. strace shows this: futex(0xb76dcae8, FUTEX_WAIT, 2,
NULL
...
How can I resolve this?
I see that one suggestion is rm /var/lib/rpm/__db*. How do I rebuild it
then?

You can just remove the __db* files (if you're sure they're there because of an rpm interrupted process, check first if there are no rpm processes running). __db* are Berkeley DB's lockfiles and are used for transactions inside Berkeley DB. You don't need to rebuild anything, the RPM database is on the other files on that directory. Once you remove the locks you'll be able to access it normally.
 
I found that cleaning the metadata doesn't remove the sqlite databases, so
I removed these from /var/yum/cache as well. The rebuilt databases were
different, but it didn't solve the problem.

You don't have to clean /var/yum/cache since that's yum's cache and the problem you have is with rpm. Cleaning it, however, won't hurt you, you'll only have to download the RPM again.

Hope it helps,
Filipe