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How to reduce DASD utilization

adamsmw
adamsmw asked
on
My DASD is at 80% utilized.

Are there common things that I can delete? Can you provide me with some example commands?

We are running iSeries V5R4.

Thanks
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VP Technology / Senior Consultant
Commented:
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
Gary PattersonVP Technology / Senior Consultant

Commented:
Feel free to post disk usage reports here, and we can help give more specific advice cleanup candidates on your specific system.

Use the Windows-based iSeries Navigator program to convert your reports to text format.

-Gary Patterson

Check out me EE profile:  http://www.experts-exchange.com/M_4382324.html
>  Start with disk space usage reporting from the  DISKTASKS menu.

That is particularly important advice. I often see newer systems with the majority of space taken up by /root file system streamfiles. They may be a minority of systems, but they aren't well served by the old standard "cleanup" options.

The point is that if you don't know what's using your space, then your cleanup efforts may be a waste of time.

So -- start with the advice about usage reporting!

Tom
Gary PattersonVP Technology / Senior Consultant

Commented:
Once I've gathered my usage info, I always focus on the "Big Stuff" first: largest QSYS objects, largest libraries, users with the largest disk usage, largest IFS folders, largest IFS folder and subtrees, files with largest number of bytes in deleted space, etc.

- Gary