The information from the 2006 post is incorrrect. For a 4K blksize & no keys, a cylinder holds exactly 720K, as DASDCALC says, not 780K.
4096 * 12 blocks * 15 tracks = 737280 = 720K Also, it is inexact wording to say "According to DASDCALC, a cylinder with a blksize of 4096 is 830K" because that implies the blksize was a factor used in arriving at the 830K figure. In fact the box where DASDCALC shows 830K (when the Cylinders box is set to 1 and units are set to KB) does not change when you change the value in the Blksize box. It remains at 830K for any blksize value because that box just represents 100% usage of each track, or the capacity if each track contained a 56664-byte block. Bill On Tue, 23 Dec 2008 16:10:55 -0600, Mark Zelden wrote: >Different year... same thread. > >I saw a similar thread in the archives from November 2006. >"MB to Cyl Conversion" > >On of the posts said this: > >For 3390 DASD: >- A cylinder holds exactly 780 KB (based on 4K blksize & no keys) >- to store 1 MB of 4K blocks requires 1.3128 CYLs >- 1 CYL = .76171875 MB > >http://bama.ua.edu/cgi-bin/wa?A2=ind0611&L=ibm- main&D=1&O=D&P=246633 > >According to DASDCALC a cylinder with a blksize of 4096 is 830K and >effective kilobytes is 720K. > ---------------------------------------------------------------------- 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
