Although DCOLLECT is restricted where I work, so I've never been able to actually use it, I believe it's the simplest and easiest option for this task, if available. See DFSMS Data Collection Facility: http://publibz.boulder.ibm.com/cgi-bin/bookmgr_OS390/BOOKS/dgt2i2a1/11.0
For my own homegrown solution for this requirement, I use the UCBSCAN service to allocate each online volser (one at a time), then run through the DSCBs in each VTOC and write out the information I want, including the calculated size of each individual extent. Then, sorting the output by DSNAME and summing the extent sizes, I can obtain a precise value for the number of tracks used by each Dataset. Then, sorting by total size in descending order, I can identify the largest datasets on the entire system. For convenience, I also write the output to a .csv format file where it can then be easily manipulated for further analyis. A detailed discussion of the development of this solution can be found here: http://www.linkedin.com/groups/1462937/1462937-220206787 ... along with some other goodies, such as how to use EXCP. I can share the code for it if you like, but be forewarned it's written in Assembler, so the code is likely to be gibberish unless you have good understanding of the language. Nonetheless, if you don't mind Assemble the code with the standard IBM ASMA90 Assembler, and Bind (Link) it into a load library, it *will* run and *will* work. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
