It really depends on your retore needs. Directories are a special case of
"small files". Restore performance from tape, especially for lots of small
files, will vary depending on whether you collocate by file space or node,
or if you don't collocate at all; plus how well tapes are managed via
reclamation. Storing the directories on disk will likely benefit most those
who do not collocate at all. If you back up solely to disk, then DIRMC is
probably not of significant value. As with anything else, your mileage may
vary.

Pop quiz: "TSM is designed to always restore directories first, then the
files." True? or False?

Answer: FALSE. TSM restores objects in such a way that it tries to optimize
tape mounts. If a file is restored before its parent directory and the
directory does not exist, then TSM will create the directory (using default
attributes) and restore the file therein. Assuming the parent directory is
included in the restore specification, the directory will be restored
later.

Note: "BOTH" is also an acceptable answer if you qualified it thus: Back in
the early days of TSM, when it was called ADSM, the product did indeed
restore directories first, then the files. At the time, the major impacted
OS was NetWare because its directories were backed up to storage pools
rather than contained in the TSM server database. So DIRMC was helpful for
NetWare. If memory serves, Windows NT was not supported initially by ADSM
(probably because the OS wasn't yet GA when ADSM was being developed), but
DIRMC eventually became useful for the Windows NT NTFS file system.

Andy Raibeck
IBM Software Group
Tivoli Storage Manager Client Product Development
Level 3 Team Lead
Internal Notes e-mail: Andrew Raibeck/Hartford/IBM@IBMUS
Internet e-mail: storman AT us.ibm DOT com

IBM Tivoli Storage Manager support web page:
http://www.ibm.com/software/sysmgmt/products/support/IBMTivoliStorageManager.html


The only dumb question is the one that goes unasked.
The command line is your friend.
"Good enough" is the enemy of excellence.

"ADSM: Dist Stor Manager" <ADSM-L AT VM.MARIST DOT EDU> wrote on 10/15/2009
05:02:34 AM:

> [image removed]
>
> DIRMC
>
> Bill DOURADO
>
> to:
>
> ADSM-L
>
> 10/15/2009 05:03 AM
>
> Sent by:
>
> "ADSM: Dist Stor Manager" <ADSM-L AT VM.MARIST DOT EDU>
>
> Please respond to "ADSM: Dist Stor Manager"
>
> Hi All,
>
> Is DIRMC still useful ? Or should I ditch it.
> Windows clients only.
> Storage Management Server for Windows - Version 5, Release 4, Level 2.0
>
> Many Thanks
>
> Bill Dourado