We went from z14 to z15's and didn't notice any difference in compression. I would be curious to see listcat of both showing the user data size and the comp data size as well as the dataset DCB attributes.
-----Original Message----- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] On Behalf Of PINION, RICHARD W. Sent: Thursday, July 22, 2021 3:55 PM To: IBM-MAIN@LISTSERV.UA.EDU Subject: zEDC compression on z13 and z15 We migrated from a z13 to a z15 this past weekend. We are running z/OS 2.2, z/OS 2.2 on the z13, and the same z/OS 2.2 on the z15. z15 maintenance was applied to z/OS 2.2, and activated a couple of months ago. We are using the same SMS configuration on the z15 as the z13, and that includes the zEDC compression Data Class. I restored a dataset that was created on the z13 using zEDC compression, and needed to make a copy of the dataset on the z15. I was surprised to see an almost 20,000 track difference between the z13 created dataset, and the z15 created dataset. I used the same SMS Data Class to make the z15 version of the dataset. Enter "/" to select action Tracks %Used ------------------------------------------------------------------------ Z13.CREATED.DATA.SET 47550 99 Z15.CREATED.DATA.SET 64555 100 SMS allocation messages for the z15 created dataset follows. IGD17070I DATA SET Z15.CREATED.DATA.SET ALLOCATED SUCCESSFULLY WITH 1 STRIPE(S). IGD17160I DATA SET Z15.CREATED.DATA.SET IS ELIGIBLE FOR COMPRESSION IGD101I SMS ALLOCATED TO DDNAME (SYSUT2 ) DSN (Z15.CREATED.DATA.SET) STORCLAS (STANDARD) MGMTCLAS (DE180DAY) DATACLAS (COMP) VOL SER NOS= TL0018 I have not looked into the TCB/SRB I/O numbers of the z13 creating job to compare against the z15 job. Anyone have an idea as to why such a dramatic difference? Confidentiality notice: This e-mail message, including any attachments, may contain legally privileged and/or confidential information. If you are not the intended recipient(s), or the employee or agent responsible for delivery of this message to the intended recipient(s), you are hereby notified that any dissemination, distribution, or copying of this e-mail message is strictly prohibited. If you have received this message in error, please immediately notify the sender and delete this e-mail message from your computer. ---------------------------------------------------------------------- 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
