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Dump

PostPosted: Tue Mar 19, 2013 11:02 am
by pearl
what is a dump? I know that there are different types of dumps. But, could someone explain them to me in simple terms?
Thank You.

Re: Dump

PostPosted: Tue Mar 19, 2013 12:46 pm
by NicC
What did you find on Google? Z/OS dump - second item returned (when I queried it)

Re: Dump

PostPosted: Tue Mar 19, 2013 12:52 pm
by enrico-sorichetti
You might find useful to read and meditate on
http://www.redbooks.ibm.com/abstracts/sg246366.html

and later proceed to
http://www.redbooks.ibm.com/abstracts/sg246981.html
( the first one of the series )

Re: Dump

PostPosted: Tue Mar 19, 2013 10:12 pm
by dick scherrer
Hello,

Dumps are the content of some storage (memory or media) that are usually formatted for readability.

The content shown depends on the type of dump and what was dumped.

This topic is too nebulous for a forum question (unless i misunderstand what you are looking for).

Re: Dump

PostPosted: Wed Mar 20, 2013 1:12 am
by c62ap90
In my opinion raw Dumps are not formatted for readability. If you have a Dump "product" like Abend-Aid then you get some formatting for readability. Both raw and "product" dumps are useful. Learning how to read them is another story.

Since your question is so general, here is a general answer…
http://www.webopedia.com/TERM/D/dump.html

Re: Dump

PostPosted: Wed Mar 20, 2013 1:20 am
by Robert Sample
Different dumps are formatted in different ways. An LE dump, for example, is human-readable whereas a system dump needs IPCS to make sense of it.

Re: Dump

PostPosted: Wed Mar 20, 2013 10:25 pm
by pearl
Thank you everyone for helping me. :)

Re: Dump

PostPosted: Thu Mar 21, 2013 5:08 am
by steve-myers
In OS/360 based systems there are 4 types of storage dumps after an abnormal program termination all users have accessed to.
  1. LE (Language Environment) dumps. These are generally printed, and show basic Language Environment information.
  2. Summary dumps
    A summary dump is presented to a user in the JESMSGLG data set. You generally see the registers, the location of the last instruction executed, sometimes formatted to show the load module and offset in the load module where the instruction is located, though this information is often incorrect and 12 bytes of storage, from 6 bytes before the location counter to 6 bytes after the location counter.
  3. SYSUDUMP/SYSABEND dumps.
    These dumps are printed dumps. The terms SYSUDUMP and SYSABEND refer to the DD statement on which the dumps are printed. Both dumps display many system control blocks related to the user's address space. In my opinion the usefulness of the control block portion of the dump has been negated by formatting many control block that do not appear to be relevant to the problem. Both dumps show storage. Historically, a SYSUDUMP dump displayed all allocated user storage, and SYSABEND dumps displayed some system storage in addition to the allocated user storage. In MVS systems the contents of these dumps are controlled by system options set by the systems programmers, so the contents of the dumps may not be the same as earlier systems. In most places SYSUDUMP dumps stay reasonably true to the traditional model, but SYSABEND dumps are often the same as SYSUDUMP dumps.
  4. SYSMDUMP
    A SYSMDUMP dump is unformatted binary data directed to a data set specified by the SYSMDUMP DD statement rather than printed. You must use a program called IPCS to process these dumps, either interactively at a TSO session, or by running TSO in batch to produce printed reports. Using IPCS effectively requires considerable knowledge of IPCS and the system. Once you have learned IPCS it is usually easier to dig out relevant data than by trying to dig through a printed dump.
Now I have talked about using the SYSUDUMP, SYSABEND and SYSMDUMP DD statements to determine the type of dump. If more than one of these DD statements is present, the system uses the last DD statement for the job step. See the "MVS JCL Reference" manual for your z/OS release.