I'd personally go for a larger CI size, like 12K (12288) or 26K (26624). Storage (both DASD & virtual) is no longer a problem. I think for 26K CI size VSAM will actually store CIs in 2K physical blocks, for 12K CI size - VSAM will store a CI in 4K physical blocks (best 3390 geometry DASD track utilisation). Hth...
-----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of Mowry, Norma E CIV DISA ESB (US) Sent: Thursday, June 06, 2013 3:24 PM To: [email protected] Subject: Question on INFOMAN VSAM files Within Infoman (version 7.1) there is a ultility (blgut20) that runs an analyze on a database file (SDDS). This gives the following information: SDDS DATA SET ANALYZED: 'SYS3.INFOMAN.MC.SDDS' TIME: 07:07:12 DATE: 06/04/2 CI SIZE: 4096 KEY LENGTH: 7 MAXIMUM RECORD LENGTH: 4089 TOTAL DATA SET SIZE: 345860821 TOTAL SDDS STRUCTURED DATA SIZE: 200358530 TOTAL SDDS STRUCTURED TEXT SIZE: 62696938 TOTAL SDDS STRUCTURED HISTORY SIZE: 82805353 LOGICAL RECORDS PROCESSED: 61555 PHYSICAL RECORDS PROCESSED: 123082 MINIMUM SDDS LOGICAL RECORD SIZE: 757 AVERAGE SDDS LOGICAL RECORD SIZE: 5619 MAXIMUM SDDS LOGICAL RECORD SIZE: 281514 SDDS RECORDS REQUIRING A 512 CI SIZE: 0 SDDS RECORDS REQUIRING A 1024 CI SIZE: 1 SDDS RECORDS REQUIRING A 2048 CI SIZE: 62 SDDS RECORDS REQUIRING A 3072 CI SIZE: 1670 SDDS RECORDS REQUIRING A 6144 CI SIZE: 48134 SDDS RECORDS REQUIRING A 8192 CI SIZE: 8186 SDDS RECORDS REQUIRING A GREATER THAN 8192 CI SIZE: 1956 SDDS RECORDS REQUIRING MULTIPLE CONTROL INTERVALS: 58276 SDDS ANALYZE UTILITY COMPLETE We ran into a problem where our dataset is running into high extents and I was wondering if I should change the CI size in the define to a size where most of the records are (6144). We currently use the product provided value of 4096. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
