>On an active system the size of the dump file can vary up and down if >you are using the SPXTAPE command to offload spool files for spool >backups. CP will use some of the dump space to keep track of the files >it is dumping (can you tell I've "been there, got the ETR t-shirt"). CP >will give back the pages used by SPXTAPE when your system gets busy, or >you can turn off the dumps and turn them back on again (SET DUMP OFF and >SET DUMP DASD) to free them up right away.
CP does not use dump space to keep track of files being dumped by SPXTAPE. The amount of allocated dump space increases and decreases based on the amount of storage being used. Since SPXTAPE uses a significant amount of storage, it is typical that the amount of dump space will increase when SPXTAPE is used. But SPXTAPE is not the only system function that uses storage and causes the amount of storage to increase. You will likely see the amount of allocated dump space increase over time whether you use SPXTAPE or not. Another thing to be aware of is that frames of storage that are used by CP are not returned until CP needs them for something else. So you will not see an immediate decrease in storage (or dump space) allocation just because SPXTAPE or some other function you are running completes. John Franciscovich z/VM Development
