On Thu, 16 Feb 2012 23:57:44 -0800, Edward Jaffe <[email protected]> wrote:
>On 2/13/2012 9:38 AM, Joel C. Ewing wrote: >> Requiring application programmers to think in terms of tracks and cylinders >> and to understand interaction between physical block size and track capacity >> is indeed archaic, as are artificial restrictions on number of extents or >> volumes. > >TRKs and CYLs? Most of our allocations are in MEGs. Doesn't everyone do that >these days? > >SPACE=(1,(5,1),RLSE),AVGREC=M Allocate in MEGs > > Not that I've seen. A good portion of production JCL just uses a dataclas for various allocation amounts / defaults like "MB100E" (100MB, extended format). But most production and almost all end user JCL (including sysprogs like myself) still use CYL. Maybe because I just copy other JCL to start with, and I guess I can just "picture" the amount it represents in my head. Although it is a crude and inaccurate conversion, one could use M instead of CYL basically 1:1 and would be sure to get enough space since 1M is about 1.42 CYLs. If I did that at least I could picture it in my head the same way I have been doing with with CYL for my entire MF career. On a slightly larger scale, so what if I allocated in M and ended up with 710 CYL instead of 500 CYL. (typical for me to use (500,500) for "large-ish" allocations). Mark -- Mark Zelden - Zelden Consulting Services - z/OS, OS/390 and MVS mailto:[email protected] Mark's MVS Utilities: http://www.mzelden.com/mvsutil.html Systems Programming expert at http://expertanswercenter.techtarget.com/ ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
