PDS's have the reclaiming space issue, PDSE's should not. With a PDSE when a member is deleted, or re-written to a larger block, the unused space it had occupied becomes available for immediate usage by the next write (STOR) activity. It maintains a list of free blocks in the directory, nothing, including a library in a linklist or a CICS region should be preventing that from being updated.
If a system is not doing this it is likely because there is a user exit or SMS exit preventing it, or maybe forcing PDSE allocations to be a PDS's. The only time a PDSE might need a reorg itself, is when it has split the library's directory over all the extents it has allocated. This really only happens in a heavily used source library. As for IEBCOPY it needs a 3meg region size minimum when working with PDSE's, as opposed to the 450K size when working with PDS's Darren -----Original Message----- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] On Behalf Of Paul Gilmartin Sent: Wednesday, August 15, 2007 1:40 PM To: [email protected] Subject: Refreshing PDSEs (was: linklisted load library failing) On Wed, 15 Aug 2007 14:57:16 -0500, Patrick O'Keefe wrote: Then, how much space does it take to refresh a PDSE by complete replacement by IEBCOPY? 200% of the quiescent size? Or does IEBCOPY somehow cleverly optimize the space requirement. But this is for integrity in case: Address space A does a BLDL, FIND, or NOTE. Address space B replaces or deletes the member that address space A found. Address space A then POINTs at the member. But nowadays, {Z|H}FS directories are supported (read only) as libraries by BPAM. What then happens in the analogous case, replacing PDSEs by UNIX directories? Does the POINT or subsequent READ fail as some sort of invalid reference? Or does the NOTE cause the open() of a descriptor of the underlying file, anchoring it in place (although I might expect that unlike a library member it might nonetheless be overwritten by a concurrent process)? -- gil ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
