Noted, 32760, truncated to a multiple of LRECL, reduces the number of calls.
PDSE won't reblock if the dataset isn't PDSE. Or are you saying that FORCE SYSTEM DETERMINED BLOCKSIZE only applies to PDSE? -- Shmuel (Seymour J.) Metz http://mason.gmu.edu/~smetz3 ________________________________________ From: IBM Mainframe Discussion List [[email protected]] on behalf of Paul Gilmartin [[email protected]] Sent: Wednesday, March 3, 2021 11:43 AM To: [email protected] Subject: Re: TSO RECEIVE and System Determined Blksize - New RFE On Wed, 3 Mar 2021 15:58:28 +0000, Seymour J Metz wrote: >32760 is optimal for load libraries; I don't know of any reason to use it for >PDSE. > 32720 (as below) for FB80 minimizes overhead of calls to READ at the expense of greater REGION. There's no concern of wasted space with PDSE 4Ki pages. 27920 has no advantage for PDSE >I would expect FORCE SYSTEM DETERMINED BLOCKSIZE to break things, and not just >for RECEIVE. Consider old programs with hard wired buffer sizes and other >programs creating output for them. If SDB increases the block sizes for the >creating programs, the reading programs will fail on S001. > PDSE will reblock for the hard wired buffer size. >________________________________________ >From: Wendell Lovewell >Sent: Wednesday, March 3, 2021 10:35 AM > ... >Since IEBCOPY is adjusting the blksize, it must be that RECEIVE did the >allocation first and deallocated the empty file. Then SDB says "I can do >better" & changed the blksize. Then when IEBCOPY is called it says "that's >not right, I'll fix it". Makes me wonder if anyone uses SDB. Plus, how is >32720 an "optimal" block size? Optimal for disk sales? :) -- gil ---------------------------------------------------------------------- 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
