Re: Object Compression

["Al Barsa, Jr." <barsa2@xxxxxxx>]

At 10:14 PM 4/29/99 -0400, you wrote:
>>At 05:44 PM 4/29/99 -0500, you wrote:
>>>>Do you have any experience with the CPROBJ command? If yes, please
>>>>share it with us.
>>
>>>>4. What is the 'dark side' of this command?
>>
>>It can cause SYSTEMPERFORMANCE(*DOWNTHETOILET).
>>
>>Al Barsa, Jr.
>
>
>Al, do you mean because needed objects will have to be un-compressed?  I
>was under the impression that I could safely compress 'everything.'  Then,
>as objects are actually -used-, they will be uncompressed and will be left
>uncompressed.

A compressed object is decompressed for use, and this is a relatively CPU
intensive event.  To permanently decompress it, you must use the Decompress
Object (DCPOBJ) command.
>
>I realize that compressing things in QSYS is something not for the
>faint-hearted, but as far as user data and program product libraries are
>concerned, will compressing things really cause that much trouble?

Just overhead.
>
>Doesn't IBM ship the operating system in compressed format, and only
>uncompress the parts needed?  Or does it uncompress whatever it has room
>for?

QSYS is shipped compressed.  This change was made for the increasingly
large size of QSYS during the CISC days, and the number of (9402/4) systems
with 630 and 945 MB if disk.  

After a release upgrade, the system will decompress QSYS is there is a
certain amount of DASD available.  That amount was 500MB when this feature
was added, but I have to think that it has been subsequently raised.

Al


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Al Barsa, Jr. - Account for Midrange-L
Barsa Consulting, LLC.  
400 > 390

Phone:  914-251-1234
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