Michael, Your comment doesn't seem relevant to me. Even if it takes two microseconds, it can span a time boundary which you are not including. More puzzling to me is why don't you want to get your calculation correct?
Tom Harper -----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of Micheal Butz Sent: Thursday, February 03, 2011 12:39 PM To: [email protected] Subject: Re: STCK vs TIMUSED If the code that I marking either Wall or CPU takes longer than 1 second there is big trouble Sent from my iPhone On Feb 3, 2011, at 1:21 PM, Sam Siegel <[email protected]> wrote: > On Thu, Feb 3, 2011 at 10:11 AM, Micheal Butz <[email protected] > >wrote: > >> I am doing this in Rexx exec processing a SVC dump after calling >> BLSUXTOD. To convert the double word to a 26 character string I use >> the >> last 6 digits I understand I can bypass this conversion and just do >> the >> subtraction as you said on the double word regardless wouldn't the >> results >> be the same. ??? >> >> By using the right most digits there can be a situation where the >> end-time > appears to occur prior to the start-time. Consider the following: > > Start time: 1 999 998 > End time: 2 000 003 > > When all digits are considered, end-time is greater than start- > time. When > only 6 digits are considered, start-time appears to be greater than > end-time. > > To get an accurate time enough digits need to be used to ensure that > end-time is greater than start-time when doing the subtractions. > > Using all digits as Ed has suggested pretty much guarantees end-time > will be > great than start-time. > > > >> Sent from my iPhone >> >> On Feb 3, 2011, at 11:57 AM, Edward Jaffe <[email protected] >> > >> wrote: >> >> On 2/3/2011 8:41 AM, Micheal Butz wrote: >>> >>>> I do a substr to get the last 6 digits of the date/time. The >>>> microseconds >>>> portion. And substract. Value = after - before >>>> >>> >>> To subtract TOD values, use unsigned binary doubleword arithmetic. >>> If you >>> want resolution to microseconds, shift both doubleword values >>> right by 12 >>> bits before subtracting. >>> >>> -- >>> Edward E Jaffe >>> Phoenix Software International, Inc >>> 831 Parkview Drive North >>> El Segundo, CA 90245 >>> 310-338-0400 x318 >>> [email protected] >>> http://www.phoenixsoftware.com/ >>> ---------------------------------------------------------------------- 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
