Note that the data of the files in a DIRCONTROL directory are NOT paged
to/from CP paging areas;  When referenced, CP directly pages them in from
the SFS minidisks (when the dataspace is constrcuted, the SFS server tells
CP which page in the dataspace corresponds to which minidisk block).  The
storage used by the FST's will be backed by CP's paging area's.

A reason to only place only seldom changed files in a DIRC is that each time
a file is changed, an ACCESS of the DIRC will cause a new dataspace being
created.  The ultimate, bad, result for a DIRC that is frequently changed is
that every user of it would have its own copy.  QUERY ACCESSORS dirid
(DATASPACE will tell you how many different levels are active at a given
time.

2007/7/16, Michael Coffin <[EMAIL PROTECTED]>:

Hi DK,

Wow, so if I have a DIRCONTROL directory with 100Gb of data, I'd need to
have enough storage (main, expanded and paging) for the ENTIRE 100Gb +
FSTs?  Darn, I can't see how Dataspaces could be effectively used except
in situations where you have very small directories/contents and/or very
large total storage.  I do see the advantage of the XC machines
"sharing" the contents, and in using the paging I/O routines - but the
OVERALL price would just be too high for what I had intended it for.

Maybe I can do this for just a few smaller but often referenced
directories.

Michael Coffin, President
MC Consulting Company, Inc.
57 Tamarack Drive
Stoughton, Massachusetts  02072


--
Kris Buelens,
IBM Belgium, VM customer support

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