Betsy,

Picture how much space an aggregate takes up on a physical tape at time of
backup.

(An aggregate being a collection of files).

 As files (data) expires within that aggregate the logical occupancy
decreases, however the physical space occupied by the aggregate is the same,
until the tape is reclaimed. Once it is reclaimed the aggregate is then
rebuilt and logical and physical occupany should be pretty much the same.

At least that's the way it appears to me...

Nathan



        -----Original Message-----
        From:   Moir,Betsy [SMTP:betsy.moir AT ABBOTT DOT COM]
        Sent:   Friday, October 08, 1999 8:04 PM
        To:     ADSM-L AT VM.MARIST DOT EDU
        Subject:        Re: Occupancy?

        So, after reading that, I can understand why the question was asked.
That
        didn't clear up anything.  Is a logical file the space defined for
storing a
        file and a physical file the actual physical space being used for
that file?




        ADSM-L AT VM.MARIST DOT EDU on 10/08/99 10:31:15 AM
        Please respond to ADSM-L AT VM.MARIST DOT EDU @ INTERNET
        To: ADSM-L AT VM.MARIST DOT EDU @ INTERNET
        cc:
        Subject: Re: Occupancy?

        Wanda:

        The following definitions are taken from the Glossary
        of the ADSM V3R1 Sun Solaris Admin Reference:

        logical occupancy.  The space required for the storage
        of logical files in a storage pool. Because logical occu-pancy
        does not include the unused space created when
        logical files are deleted from aggregates, it may be less
        than  physical occupancy. See also  physical file and
        logical file.

        logical file.  A client file stored in one or more server
        storage pools, either by itself or as part of an aggregate
        file. See also  aggregate file and  physical file.

        physical file.  A file, stored in one or more storage
        pools, consisting of either a single logical file, or a group
        of logical files packaged together (an aggregate file).
        See also  aggregate file and  logical file.

        physical occupancy.  The occupancy of physical files
        in a storage pool. This is the actual space required for
        the storage of physical files, including the unused space
        created when logical files are deleted from aggregates.
        See also  physical file,  logical file, and  logical occupancy.




        At 10:41 AM 10/8/99 -0400, you wrote:
        >In the OCCUPANCY SQL table there are two columns named
"physical_MB" and
        >"logical_MB".
        >Can sombody tell me the difference?
        >
        >Thanks.
        >

>************************************************************************
        >Wanda Prather
        >The Johns Hopkins Applied Physics Lab
        >443-778-8769
        >wanda_prather AT jhuapl DOT edu
        >
        >"Intelligence has much less practical application than you'd think"
-
        >Scott Adams/Dilbert
        >Scott Adams/Dilbert

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        >
        >

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