Gilbert, What is your device geomtery on your CDS BASE DISPLAY? For 3390 it should be 56664 bytes per track and 15 tracks per cyl. If it were set to 3380, I would expect your allocations to be approx 20% smaller than requested. Where in the manual did it tell you not to use Cyls? I've been using Cyls or Tracks for years with no problem. 43 cyls for 30 MB is about right. Might depend on your Cisize.
________________________________ From: Gilbert CardenasSent: Wed 4/16/2008 1:28 PM To: [email protected] Subject: SMS allocation in Cylinders using AMS Hello everyone, I have an unknown that I have not been able to figure out or at least I don't know where to look. I have a user who is trying to define a vsam file using IDCAMS as follows: DEFINE CLUSTER - ( NAME(BLAH.BLAH.BLAH) - LINEAR - REUSE - CYL(30) - SHAREOPTIONS(3 3) ) - DATA - ( NAME(BLAH.BLAH.BLAH.DATA) - ) - CATALOG(BLAH) The problem is, when I look at the dataset (which is SMS managed) it usually ends up being around 3 times larger than what the user requested. Of course the first place I looked was in the dataclas that this dataset gets assigned and the only thing that the dataclas specifies is a volume count of 1. There are no overrides anywhere else for primary or secondary space. Looking at the Access Method Services documentation, it states that you should not use the TRACKS or CYLINDERS parameters. If you use them for an SMS-managed data set, space is allocated on the volumes selected by SMS in units equivalent to the device default geometry. Could the reason that this dataset is being allocated larger than requested have to do with the fact that the sms volumes are mod 9 volumes? Btw, I tried allocating the dataset in Megabytes (30) and I got 43 cyl with 1 extent. I don't know what the conversion of megabytes to cylinders is but this still doesn't seem right. Regards, Gil. ---------------------------------------------------------------------- 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
