Hi Peter, I don't think anybody answered this question. With modern (read: emulated) boxes I've been told the location of the VTOC/VTOCIX/VVDS don't matter anymore. Back in the SLED days I was a stickler for placing the VTOC & IX 1/3 of the way into the volume, right next to each other to try to minimize head movement. Now, with it all placed on "smoke and mirrors", and with huge cache sizes, the location doesn't matter, so I place them right at the beginning of the volumes so that I have the largest possible contiguous free space - at least until the first dataset on the volume is deleted. :-)
Rex -----Original Message----- From: IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU> On Behalf Of Peter Sent: Saturday, July 4, 2020 11:22 PM To: IBM-MAIN@LISTSERV.UA.EDU Subject: [External] Re: Vtoc and index sizing based on Mods Hello Thank you so much How do we determine the location of vtoc and index ? Is it possible to place all the mod 27 in same location of cylinder and tracks ? On Sat, 4 Jul, 2020, 9:44 PM Lizette Koehler, <stars...@mindspring.com> wrote: > It depends > > If the volume would have one dataset on it, like my SPOOL Volumes, > then they are very small > > If like in my TSO Pool there are lots of tiny (15 track or less) then > I make them huge. > > So it all depends on > > What the intent of the volume is (1 dataset vs Many Datasets) What > size the volume is (Mod3/9/27/54/EAV) > > You will see an error message when the VTOC or VTOIX is too small. > > > > Hope this helps > > Lizette > > > -----Original Message----- > From: IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU> On > Behalf Of Peter > Sent: Saturday, July 4, 2020 10:12 AM > To: IBM-MAIN@LISTSERV.UA.EDU > Subject: Vtoc and index sizing based on Mods > > Hello Group > > Apology for being ignorant. > > Is there a formula or any constraints for initialising a specific dasd > Mod ? > > How do arrive to a specific vtoc and index value while initialising a > dasd ? > > Please help me to understand > > Peter > > ---------------------------------------------------------------------- > 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 > ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN The information contained in this message is confidential, protected from disclosure and may be legally privileged. If the reader of this message is not the intended recipient or an employee or agent responsible for delivering this message to the intended recipient, you are hereby notified that any disclosure, distribution, copying, or any action taken or action omitted in reliance on it, is strictly prohibited and may be unlawful. If you have received this communication in error, please notify us immediately by replying to this message and destroy the material in its entirety, whether in electronic or hard copy format. Thank you. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
