We had the same thing happen to us about a week ago. Still waiting on the Root Cause. We ran the "service show process" command and saw the CFGD process taking 99% for more than 24 hours. So far Support is saying a script was running and got hung up. Like I said though, we are still waiting on the root cause after we uploaded all tech-support files before reloading the controller. Since the reload, all has been good.
Suggest you get a case open before you reload and do a "service copy tech-support ftp://xxx.xxx.xxx/file-name to a local drive. When you open the case you can upload the tech-support file for them to analyze.