Disk Space Manager

Because of the very large number of objects it is very difficult to manage them manually. Inactive objects clutter the disk and active objects may use more space than they need.

DSM helps you to identify the problem by printing exception reports which allow you to concentrate only on the objects which need attention. It has tools to let you reclaim the wasted disk space.

• IBM System Objects

  IBM System objects, in principle, should not be touched. When shipped they are already at their minimum size. However some system libraries such as QGPL, QRECOVERY and QRPLOBJ require periodic inspection and cleanup.

• Active User Objects

  These objects can be reduced in size by using one of these techniques:

  • Source or data physical files can be compressed
  • Programs can have observability removed
  • Data physical files can be reorganized

  Compressing source files shrinks their sizes typically by more than 50%. DSM uses a very fast machine interface (assembler-type) operation to perform the compression and decompression. Data physical files may be compressed similarly but must be decompressed before being used. Reoganizing data physical files brings variable savings depending on the particular file. Removing program observability reduces their sizes by up to 70%.

• Inactive User Objects

  These objects should be deleted with or without prior backup. DSM helps you positively to identify inactive objects.

  DSM looks at some big disk space eaters. Save files and journal receivers are two of them. Spooled files yet another. When you delete a spooled file, the operating system leaves an empty physical member in library QSPL waiting to be reused. Some installations have hundreds or even thousands of these inactive members doing nothing except occupying valuable disk space.

  When DSM deletes a spool file it deletes the whole thing including these empty members.

  DSM also analyses the history log and problem log.

• Duplicate Objects Analysis

  Large space savings can be achieved by removing duplicate objects. Many times objects or even whole libraries are duplicated just for a quick test but when the test is completed the duplicate objects stay on disk unnoticed.

  DSM has special options to find duplicate objects. If both objects have the same name, DSM will trap them. If they have different names but the same root name (e.g. ITEM and ITEMOLD) DSM prints reports where they appear closely enough together to allow the expert eye to spot them.

• Disk Space Analysis

  This function allows you to print eighteen reports with several levels of summary/detail.

  • Library Name Summary
  • Object Type Summary
  • Object Attribute Summary
  • Object Name Detail

  In each report you may select the range of libraries and object types/attributes to include or exclude. A convenient selection allows you also to exclude objects and/or libraries below a minimum size.

  Reports may be printed either in the conventional alpha sequence or in descending object size sequence.

  For example, a very popular option is a short report that lists libraries in descending library size sequence. Report options may be saved for later use.

• Reclaim Space Analysis

  This function prints nine reports which allow you to perform a "what if" analysis on your objects. For example, how much space do I save if I delete all superceded save files? Or, if I delete all spooled files more than 30 days old?

• Reclaim Disk Space

  This option includes ten commands you can use to clean up your disk.

  In principle these commands perform only either harmless or recoverable operations. For example, a command lets you remove program observability. However at a later date you can recompile the programs to make them observable again. Another command lets you delete duplicate objects but DSM first checks that an original object exists.

• Compress and Decompress

  This option lets you compress and decompress source and data physical files, operate on compressed source members (edit, compile etc.) and compress and decompress programs.

• Auxiliary Functions

  This option lets you print history reports, print/display DSM documentation and perform general maintenance of the DSM system.