What's the difference between "release" and "compress"



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What's the difference between "release" and "compress"

Postby vsevarod » Thu Jun 15, 2017 7:52 am

Hi all,
I am just confused with "release" and "compress". It seems space are freed either I use "release" command or "compress" command.
So what's the difference between the two concepts?
Thanks in advance.
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Re: What's the difference between "release" and "compress"

 

Re: What's the difference between "release" and "compress"

Postby Akatsukami » Thu Jun 15, 2017 8:00 am

"Release" de-allocates unused space from a data set; "compress" does not. Moreover, "compress" only applies to a PDS.
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Re: What's the difference between "release" and "compress"

Postby vsevarod » Thu Jun 15, 2017 10:50 am

Akatsukami wrote:"Release" de-allocates unused space from a data set; "compress" does not. Moreover, "compress" only applies to a PDS.

Thanks, so what did I do when I compressed a PDS?
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Re: What's the difference between "release" and "compress"

Postby steve-myers » Thu Jun 15, 2017 11:43 am

In a PDS, when you delete a member, the space occupied by the deleted member forms a "hole" in the data set that cannot be used for additional members. When you "compress" a PDS, these "holes" are removed so you can add more members to the data set.

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Re: What's the difference between "release" and "compress"

Postby vsevarod » Thu Jun 15, 2017 11:44 am

steve-myers wrote:In a PDS, when you delete a member, the space occupied by the deleted member forms a "hole" in the data set that cannot be used for additional members. When you "compress" a PDS, these "holes" are removed so you can add more members to the data set.

Thanks
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Re: What's the difference between "release" and "compress"

Postby willy jensen » Thu Jun 15, 2017 1:00 pm

Replacing a member in a PDS will normally also leave a hole where the old data was, even if the new data might have fitted in the space occupied by the old member.
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