The index component alone is 2.4 MB? 2,400,000/56664 = 43 tracks? Sure, Allocate the index component as 4 or even 5 cylinders primary and a single cylinder secondary.
If the cluster has changed significantly over time, I might also run an IDCAMS EXAMINE command: EXAMINE NAME(<cluster name>) INDEXTEST DATATEST And look for: IDC01728I FOUND n EMPTY CONTROL AREAS THAT HAVE NOT BEEN RECLAIMED IDC11775I nnn DATA COMPONENT CIS ARE ESTIMATED TO BE UNREACHABLE These may indicate that you want to change the index CI size, although buffer specifications may also have to change if you do. And I assume you have already activated 'CA reclaim' for all pertinent DATACLASes in ISMF. -----Original Message----- From: IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU> On Behalf Of Lizette Koehler Sent: Sunday, August 30, 2020 5:12 PM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Simple VSAM question on sizing INDEX component CAUTION: This email originated from outside of the Texas Comptroller's email system. DO NOT click links or open attachments unless you expect them from the sender and know the content is safe. List - I have a VSAM Dataset that has grown over the years. When it was set up - the INDEX space was left to default I am wondering if it makes sense to override the Track Allocation and put it in Cylinders. We are noticing a little bit of an increase in run time during reorg. I was wondering if this might be due to the data set having 3.4GB now. This file is EA/EF so it can grow Over 4500 Cylinders on the Data And the index is using tracks 2 pri and 11 sec - size is now 2.4 MB During reorg we offload records to an archive then reload the current data back in. This may be something I cannot improve on, just thought I would see if there are any insights I am missing. Process: Offload the data to a temp file Archive records older than 2 weeks Del/Def VSAM dataset Reload current records to VSAM dataset This runs daily Thank you Lizette ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN