No, the initial allocation was not in 4 extents. It was in one extent and consumed 2500 cylinders. The remaining 3 extents on the first volume are secondary extents and consume 100 cylinders each.
After the initial allocation was used up, the dataset continued to grow, by a total of 1831 cylinders. It did not obtain all this space at once. It grew by one secondary extent at a time, 100 cylinders apiece. The first 18 secondary extents provided 1800 cylinders. The last 31 cylinders were in the 19th extent and the excess space (69 cylinders) was apparently released. (How many 100 Euro notes does it take to pay for an airplane ticket costing 1832 Euros?) One initial extent of 2500 + 18 secondary extents of 100 + 1 secondary extent of 31 (19 secondary extents total) yields 4331 cylinders in 20 extents. -----Original Message----- From: William F Besnier [mailto:snip] Sent: Thursday, August 14, 2008 7:17 PM To: [email protected] Subject: Re: DASD Space Allocation -----Original Message----- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] On Behalf Of Schwarz, Barry A Sent: Thursday, August 14, 2008 6:44 PM To: [email protected] Subject: Re: DASD Space Allocation What is the LRECL, RECFM, and BLKSIZE? 4331 cylinders is 64,965 tracks. That averages to ~46 records per track. Is there some reason you think this is unreasonable? Don't think it's unreasonable, don't know what it has to do what is specified in JCL and what was allocated. What is the percentage used of the 4,331 cylinders? What is the device type the dataset is on? The dataset was allocated across 2 3390-9 volumes; 4 extents on the first volume with 100% utilization. If the initial allocation provided all 2500 cylinders in one extent, the remaining 1831 cylinders does require 19 extents so it at least that looks consistent. The initial allocation was in 4 extents. I thought for a PS file, the F1 DSCB gave 3 extent descriptors and the F3 DSCB gave another 13 extent descriptor for a total of 16 extents per volume. Please explain how 1831 cylinders requires 19 extents and that is consistent. ---------------------------------------------------------------------- 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
