(This report should relate to both "jobconfighistory" and "global-build-stats" components but latter doesn't exist in Jira)
1. Global Build Stats plugin saves log into global-build-stats.xml in Hudson home directory.
2. Job Config History plugin saves copy of global-build-stats.xml for each change in it.
Each copy of global-build-stats.xml takes about 1-3 Mb for my Hudson setup, so after few months of using both of pointed plugins "configuration history" for global-build-stats.xml took about 7 Gb of space.
Solution for this issue is to add "global-build-stats" into "system configuration exclude file pattern" in Job Config History configuration (http://HUDSON/configure).
My suggestion is to do one of:
1. Describe this issue on Global Build Stats/Job Config History plugins wiki.
2. Store log for Global Build Stats not in .xml file.