As for location, in a distant galaxy long ago, SLED DASD liked VTOC and VVDS (did that exist then?) located in the middle of the volume to minimize head movement. (Nod if you agree.) That pra
It stopped nattering long before RAID came out. 3380-K was when IBM stopped recommending it. Sent from my BlackBerry 10 smartphone on the Bell network. Original Message From: Skip Robinson Sent: Saturday, February 8, 2014 14:12 To: IBM-MAIN@LISTSERV.UA.EDU Reply To: IBM Mainframe Discussion List Subject: Re: Implicit VVDS creation Aside from the how of creating your own VVDS, I'm concerned about the why. OK, if an existing VVDS fills up, that's a why. Otherwise, you might consider creating your own VVDS at the outset if the default size or location is likely not appropriate for the volume. For example, a huge volume like a Mod-54 or any that will likely hold a myriad of small data sets might well need a larger VVDS. OTOH a volume for JES, page, or XCF data sets will likely never need more than a minuscule VVDS. As for location, in a distant galaxy long ago, SLED DASD liked VTOC and VVDS (did that exist then?) located in the middle of the volume to minimize head movement. (Nod if you agree.) That practice no longer makes sense in the era of RAID, so generally aim for the lowest address possible. Especially for JES and page volumes, location or size of VTOC and VVDS can reduce the usable space for very large single-extent data sets. In these cases, very small VTOC and VVDS (if needed) should be scrunched into the first few tracks. . . J.O.Skip Robinson Southern California Edison Company Electric Dragon Team Paddler SHARE MVS Program Co-Manager 626-302-7535 Office 323-715-0595 Mobile jo.skip.robin...@sce.com From: "Cosby, Bob - OCFO" <bob.co...@nfc.usda.gov> To: IBM-MAIN@LISTSERV.UA.EDU, Date: 02/07/2014 11:04 AM Subject: Re: Implicit VVDS creation Sent by: IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU> Just ran into a situation where the VVDS was filling up; 10,10 was not working. Our DBMB group was installing DB2 V10 which has to be SMS managed and were placing hundred of DSNs on one mod-3. So I INIT'ed them as INIT UNIT(560D) VOLID(DBJ555) VTOC(1,0,60) VFY(TS560D) - INDEX(0,1,14) STGR -----Original Message----- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] On Behalf Of John McKown Sent: Thursday, February 06, 2014 12:01 PM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Re:group Implicit VVDS creation Yes. step1 is ICKDSF. Step2 creates VVDS. On Thu, Feb 6, 2014 at 11:22 AM, David G. Schlecht <dschle...@admin.nv.gov>wrote: > Does anyone still build VVDS datasets explicitly when initializing volumes? > > I understand that the default allocation for a new VVDS is CYLS(10 10) > which saves me from having to rebuild the VVDS if it fills up. > > What is everyone else doing with VVDS datasets? Is there still a valid > argument for building them explicitly? > > > David G. Schlecht | Information Technology Professional State of > Nevada | Department of Administration | Enterprise IT Services > T:(775)684-4328 | F: (775) 684‐4324 | E:dschle...@admin.nv.gov ---------------------------------------------------------------------- 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
