Lisa, I thought about the record deletion, but even when there are only a few records left the HURBA is going to reflect the highest CI used. For VSAM KSDS there's a huge difference between empty and one record, and Ed didn't mention if it was an RRDS or ESDS.
Clever programmers and billing - for some people it was as much fun as tax avoidance. Like applications running tape to tape because they were only charged for disk space. Ron > -----Original Message----- > From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of > Linda Mooney > Sent: Friday, May 06, 2011 10:52 PM > To: [email protected] > Subject: Re: [IBM-MAIN] Do we need to implement HSM > > Hi Ron, > > > > What you say is true. I did read into the post a bit because I used to get a > lot of questions by folks who would look at the catalog entry and assume that > the candidates were already used. > > > > On the other hand, I have seen nearly empty, and empty, multivolume VSAM > datasets. Turned out that our billing system (at that time), charged for > purges and reorgs (there was a charge to run the job and charges for EXCPs) , > but not for DASD residency or space. So, a clever programmer, who really paid > attention to the billing table to the benefit of his customer (I am not being > critical of him in the the least), would delete records or move them all to a > history file, but never reorg the file. I t was a fixed length record, non- > SMS controlled KSDS . Gen erally, at the beginning of the quarter, that VSAM > file would have at most a couple of hundred records, yet still span 3 > volumes. > > > > SMF records would reveal if Ed's dataset ever had records . IDCAMS or a CA- > DISK VSAM cluster report - would reveal if it is very poorly constructed and > contains maybe 95% free space. People do make some mistakes when defining > datasets. Many shops still use very little SMS. We have a mix. We use it > for some things, not for others. > > > > CA-DISK used to be DMS when Sterling Software had it. > > > > Regards, > > > > Linda > > > > ----- Original Message ----- > From: "Ron Hawkins" <[email protected]> > To: [email protected] > Sent: Friday, May 6, 2011 2:11:36 AM > Subject: Re: Do we need to implement HSM > > Linda, > > Without Guaranteed Space all except the first volume will only be candidate > volumes until the writing records to the first volume causes it to extend to > the second and subsequent volumes. > > The case Ed described is that the dataset is empty, but it had extents across > multiple volumes, which is not the usual behavior for an empty dataset that > does not use guaranteed space. Hence my curiosity. > > I agree completely with your reply, but it does not solve the empty dataset > riddle. > > Ron > > > -----Original Message----- > > From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf > Of > > Linda Mooney > > Sent: Thursday, May 05, 2011 8:22 PM > > To: [email protected] > > Subject: Re: [IBM-MAIN] Do we need to implement HSM > > > > Hi Ron, > > > > > > > > If a VSAM dataset is allocated with a candidate list of volumes > > VOLSER=(VOL001,VOL002,VOL003 ), the datset will allocate to the first volser > > in the list, then the next, etc. The catalog entry will show all of the > > volumes, even if there is no VTOC entry there yet . Back a few years ago, > > when we had much smaller volumes, we had some large VSAM datasets (non-SMS) > > that we allocated this way. > > > > > > > > Regards, > > > > > > > > Linda > > > > > > ---------------------------------------------------------------------- > 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 ---------------------------------------------------------------------- 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
