Query regarding compressing a PDS

varunraisharma · New User Joined: 01 Sep 2005 Posts: 15 Location: Bangalore

How many times can we compress a PDS, is there any limit on that.
I got 0E37 abend due to shortage of space and i compressed my PDS using command Z and started working again, I have done this 3 times...
is there any limit on the no. of times we can compress and is there any impact on the members in the PDS.

Regards
Varun

Gautam512 · Posted: Fri Dec 23, 2005 4:36 pm

While creating a dataset make sure u have given enough size for it.When it is short of space that abend is evolved.

khamarutheen · Active Member Joined: 23 Aug 2005 Posts: 677 Location: NJ

Hi frnd,
I think it depends upon the Secondary Space that u have allocated.. i m not clear with that.. let me know if any

umeshkmrsh · New User Joined: 21 Sep 2005 Posts: 79 Location: India

Compressing a dataset rearranges the data and makes larger blocks of free memory available. Number of time we can compress PDS depends upon the number of secondary blocks defined while creation.

Correct me if wrong.

mmwife · Super Moderator Joined: 30 May 2003 Posts: 1592

When a PDS member is deleted or updated, an empty space is created where the member existed. Over time as members are deleted (and recreated) these empty spaces multiply until there is not enough contiguous space available in the PDS to satisfy the space required by the newly requested member.

Running compress rearranges the members so that they reside side-by-side and those little spaces are eliminated and become one contiguous free space at the end of the PDS.

If compress doesn't create enough contig space, you may get get an abend on the next creation or update of a member.

Brian's_song · New User Joined: 27 Dec 2005 Posts: 21

Hi mmwife,
Thanks for your explaination, do you mean that there is no limit to the times suppressing the PDS until the remain spaces can't afford the size of the newly created member ?

Pls correct if I am wrong. Thanks.

Rupesh.Kothari · Member of the Month Joined: 27 Apr 2005 Posts: 463

HI Brian's_song

Yes you are right. We can reorg PDS any number of times.

Regards
Rupesh

mmwife · Super Moderator Joined: 30 May 2003 Posts: 1592

To put ie another way, Rupesh, there will come a time when after you compress the PDS there are only 2 tracks remaining uuused.

If your new member will occupy 2 tracks or 1, things will look rosey. On the other hand if itneeds 3 or more, it's Sx37 time.

Rupesh.Kothari · Member of the Month Joined: 27 Apr 2005 Posts: 463

Hi mmwife,

Yes I also agree with you, My view is, if there is space to compress then onlyu we can compress it any times, but if there is no space then how we can compress which you already mention in your last post.