The numbers of cylinders (column 2) that can be represented by the number of bits in column 1 are correct from 7 to 14 bits, but the table has slightly wrong values from 15 bits and higher. And 7 of the values are odd numbers, which can never happen.
Bill Fairchild Franklin, TN ----- Original Message ----- From: "Mike Schwab" <mike.a.sch...@gmail.com> To: IBM-MAIN@LISTSERV.UA.EDU Sent: Tuesday, June 11, 2013 6:04:57 PM Subject: Re: Data volumes On Tue, Jun 11, 2013 at 8:30 AM, Pew, Curtis G <curtis....@austin.utexas.edu> wrote: > On Jun 11, 2013, at 8:18 AM, Paul Gilmartin <paulgboul...@aim.com> > wrote: > >> 2**18 + 2**9 + 12. A peculiar number. I wonder how they chose >> that? > > For what it's worth, that's 236 * 1113, the latter being the size of a 3390 > mod 1. I don't know why they went with 236 (2**2 * 59) though. > > -- > Curtis Pew (c....@its.utexas.edu) Highest multiple of 1113 that is under 2 ** 18 (using 18 bits of the x'ccccCCChrr' field (is c'CCHHR' for non-EAV volumes.) Here is a list of OS/360 to z/OS x.xx volumes by number of bits used for number of cylinders. http://www.hercules-390.eu/hercload.html Bits Cyls Model GB 3390-Model/ Bits used First used 7 128 0.1150 0.109 M0.11 B07 8 256 0.2300 0.218 M0.21 B08 23## (OS/360) 9 512 0.4600 0.435 M0.46 B09 3330-1 10 1,024 0.9200 0.870 M0.92 B10 3330-11 11 2,048 1.8401 1.741 M1.84 B11 3380-2 12 4,096 3.6801 3.481 M3.68 B12 3380-3 13 8,192 7.3603 6.963 M7.36 B13 14 16,384 14.7206 13.926 M14.7 B14 3390-9 12/1993 15 32,760 29.4340 27.845 M29.4 B15 3390-27 OS/390 V2.10 16 65,520 58.8679 55.689 M58.8 B16 3390-54 OS/390 V2.10 17 130,221 117.0000 110.682 M0117 B17 EAV1 18 261,555 235. 222.310 M0235 B18 EAV2 3390-EAV 2bits z/OS V1.10 19 524,223 471. 445.566 M0471 B19 EAV3 20 1,048,446 942. 891.132 M0942 B20 EAV4 3390-EAV 4bits z/OS V1.13 21 2,096,892 1,884. 1,782.264 M1884 B21 EAV5 (future) 22 4,193,784 3,768. 3,564.528 M3768 B22 EAV6 3390-EAV 6 bits z/OS V2.0x 23 8,387,568 7,536. 7,129.056 M7536 B23 EAV7 24 16,776,249 15,073. 14,259.058 M15073 B24 EAV8 3390-EAV 8 bits z/OS V2.1x 25 33,553,611 30,147. 28,519.062 M28519 B25 EAV9 26 67,108,335 60,295. 57,039.070 M60295 B26 EAV10 3390-EAV 10 bits z/OS V3.0x 27 134,216,670 120,590. 114,078.140 M120590 B27 EAV11 28 268,434,453 241,181. 228,157.226 M228158 B28 EAV12 3390-EAV 12 bits z/OS V3.1x -- Mike A Schwab, Springfield IL USA Where do Forest Rangers go to get away from it all? ---------------------------------------------------------------------- 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
