It doesn't indeed.  You need to select the good directories, and you
need to change them from FILECONTROL directories (the default) into
DIRCONTROL directories first.  A DIRCONTROL directory is a bit like a
minidisk
- only 1 user can access it R/W at the same time
- updates to a DIRC are invisible to users until they reACCESS it
- R/W or R/O grants are on a "per directory" base, instead of per file
  (i.e. you use GRANT dirid TO xyz (DIRREAD or DIRWRITE )
- in QUERY ACCESSED, the CUU field is DIRC iso DIR
So, a change from DIR into DIRC is not completely transparent, but,
even without dataspaces, the overhead is less than for a FILECONTROL
directory.
To place a DIRC into the dataspace, use DATASPACE ASSIGN.  If the DIRC
is changed when users are accessing it, and a new user accesses it in
R/O mode, SFS will create a new dataspace.  Hence: if you'd place a
frequently modified directory into a dataspace, the worst case is that
each user of it has its own Private copy of the dataspace.  QUERY
ACCESSORS dirid (DATASPACE will tell you how many levels of a
dataspace exist.

2008/9/17 Gentry, Stephen <[EMAIL PROTECTED]>
>
> Whilst looking through a recent version of the VM Quick Reference manual, I 
> came across a QUERY DATASPACE command.  We use DB2 and SFS pools so the 
> dataspace part got my attention.  I know both use DATASPACE's so, I paused to 
> check out the command.  In this case, the command applies to SFS related 
> stuff.  I issued a Q  DATASPACE on our existing pools and was a little 
> surprised to find out that none of our pools were using DATASPACE's.  So, 
> this got me more curious, and I did some reading in the SFS manual.  I have 
> all the correct entries in the user directory for my SFS servers.
>
> One of my assumptions is/was that VM and/or SFS will automatically load 
> "stuff" into dataspaces.  After doing some reading, I don't think it does, I 
> have to tell SFS to put directories into a DATASPACE.  The manual recommends 
> that SFS pools/sub-pools that are rarely updated, are good candidates.
>
> So, could someone clarify a little on this subject?
>
> Thanks,
>
> Steve


--
Kris Buelens,
IBM Belgium, VM customer support

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