System cleanup can be a complex task, and some operations require a detailed knowledge of the operating system and your applications. Before doing any cleanup, make a full option 21 backup, just in case. That said, there is usually a lot of low-hanging fruit that can be safely cleaned up, such as old spooled output, old journal receivers, old history log files, old test data and temporary files, etc.
If your applications aren't configured to reuse deleted space in database files, reorganizing files and changing files to reuse deleted space can result in big savings, but cannot be safely done in all applications. IF you find that you have a lot of deleted space in your database files, then you'll need to discuss the possibility of reorganizing the files and configuring the files to reuse deleted space with a developer familiar with your applications, or a disk management consultant that knows how to determine of reorganization/deleted space reuse is safe in your applications.
You may also be able to find obsolete libraries and objects, archive off old data (your applications may have internal archival functions that you can run regularly to clean up application files, for example), clean up test data or old versions of applications and data, and more.
Start with disk space usage reporting from the DISKTASKS menu. Also, schedule automatic cleanup from the Operations Assistant menu (GO ASSIST)
GO DISKTASKS, Collect disk space usage info, run various reports.
GO CLEANUP, configure and start cleanup, schedule automatic cleanup
Review the following articles for more information on disk space cleanup and related tasks:
http://www-01.ibm.com/support/docview.wss?uid=nas116c246792830c6b186256a5b005dcec8
http://search400.techtarget.com/tip/1,289483,sid3_gci901234_mem1,00.html
http://www-912.ibm.com/s_dir/slkbase.NSF/643d2723f2907f0b8625661300765a2a/2905aa0dabd217a186256a5b0057ef4b?OpenDocument
http://www-912.ibm.com/s_dir/slkbase.NSF/1ac66549a21402188625680b0002037e/c5f9378a8534995b86256ea000567c97?OpenDocument
http://www.itjungle.com/fhg/fhg120104-story03.html- Gary Patterson
