Well, if your new DASD architecture was manufactured in the same manner as previous DASD devices, you would have 32,769 spinning platters to deal with and an access arm with 65,535 R/W heads to move back and forth with all of the implied momentum of a device that size. How tall do you think 32K of platters would be?
HITACHI DATA SYSTEMS Raymond E. Noal Senior Technical Engineer Office: (408) 970 - 7978 -----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of Arthur T. Sent: Thursday, March 26, 2009 2:29 PM To: [email protected] Subject: Re: "A foolish consistancy" or "3390 cyl/track architecture" On 26 Mar 2009 11:54:41 -0700, in bit.listserv.ibm-main (Message-ID:<listserv%[email protected]>) [email protected] (John McKown) wrote: >Now, why is 14 tracks per cylinder so sacrosanct? Why >didn't IBM create a >new DASD with 2^16-1 (x'FFFF') cylinders where each >cylinder has 2^16-1 >(x'FFFF') tracks? And, when someone runs old JCL which requests two cylinders for a new dataset? I expect that your solution would have been easier for IBM, but many of their customers would have issues as above. -- I cannot receive mail at the address this was sent from. To reply directly, send to ar23hur "at" intergate "dot" com ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
