This following bug seems to be related to the work going on here and the frequent CPU usage spikes cause by apt-index watcher:
https://launchpad.net/distros/ubuntu/+source/libapt-front/+bug/64531 -- apt-index-watcher corrupts the apt cache database https://launchpad.net/bugs/61708 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
