Clark, I don't know where it is written up, but it has been this way as long as I can remember, which is 5 minutes when I go to the shop, and a bit longer for IDCAMS.
Following example look at the CISZ(32768) versus the physical record size (16384). Physical record size is the block size used for each record on the track, so each CI uses two blocks or records and can span a track boundary. DATA ------- HAWKINS.KSDS.DATA IN-CAT --- CATALOG.VHDSUSR HISTORY DATASET-OWNER-----(NULL) CREATION--------2018.019 RELEASE----------------2 EXPIRATION------0000.000 ACCOUNT-INFO-----------------------------------(NULL) PROTECTION-PSWD-----(NULL) RACF----------------(NO) ASSOCIATIONS CLUSTER--HAWKINS.KSDS ATTRIBUTES KEYLEN----------------44 AVGLRECL-------------435 BUFSPACE----------530432 CISIZE-------------32768 RKP--------------------0 MAXLRECL------------2040 EXCPEXIT----------(NULL) CI/CA-----------------22 SHROPTNS(3,3) SPEED UNIQUE NOERASE INDEXED NOWRITECHK UNORDERED NOREUSE NONSPANNED STATISTICS REC-TOTAL--------------0 SPLITS-CI--------------0 EXCPS------------------0 REC-DELETED------------0 SPLITS-CA--------------0 EXTENTS----------------1 REC-INSERTED-----------0 FREESPACE-%CI----------0 SYSTEM-TIMESTAMP: REC-UPDATED------------0 FREESPACE-%CA----------0 X'0000000000000000' REC-RETRIEVED----------0 FREESPC-----------720896 ALLOCATION SPACE-TYPE------CYLINDER HI-A-RBA----------720896 SPACE-PRI--------------1 HI-U-RBA---------------0 SPACE-SEC--------------1 VOLUME VOLSER------------HDSUS5 PHYREC-SIZE--------16384 HI-A-RBA----------720896 EXTENT-NUMBER----------1 DEVTYPE------X'3010200F' PHYRECS/TRK------------3 HI-U-RBA---------------0 EXTENT-TYPE--------X'40' VOLFLAG------------PRIME TRACKS/CA-------------15 EXTENTS: LOW-CCHH-----X'00060000' LOW-RBA----------------0 TRACKS----------------15 HIGH-CCHH----X'0006000E' HIGH-RBA----------720895 Ron -----Original Message----- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] On Behalf Of Clark Morris Sent: Tuesday, January 16, 2018 9:01 AM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Re: [IBM-MAIN] VSAM Performance - CPU reduction [Default] On 16 Jan 2018 06:54:52 -0800, in bit.listserv.ibm-main ronjhawk...@sbcglobal.net (Ron hawkins) wrote: >Tim, > >Things changed a couple of decades ago. > >VSAM physical block is not always the same as the CISZ. > >32K CISZ does not waste any space on the track. Where is this written up? Being retired, I missed this and didn't realize this was true on the OS390 system I worked on in the 1990s. Clark Morris > >Ron > >---------------------------------------------------------------------- >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 ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN