> Like old soldiers this topic never dies. It does not even fade away > monotonically. > > Consult the archives. The last time we went round (and round) about it > > o ROUND, while innocuous, no longer improved the performance of > sequential datasets; but > > o ROUND did still measurably improve the performance of PDSs, though > not of PDSEs. > > At that time there was a sort of commitment on the part of one of > the senior IBM posters here that he would, when he found the time, > remedy this situation, removing the exception for PDSs; and if he > has done so I am sure he will chime in to say that he has. > > The hardware issue, when DASD did indeed spin, was that allocations > in TRK units set the device mask foir an interrupt at each end-of- > track, for a run through a long block of code IOCS to ensure that > the next track was a part of in the data set being processed, while > allocations in CYL units set the device mask for this interrupt only > at each end-of-cylinder, i.e., for much less frequent runs throug this code. > > Old men and women in this business thus found themselves repeating > the litany "comma, comma, comma, round" over and over again to the > young, who had unwonted difficulty with positional parameters and > vacuous-comma coding. > > It would be nice to know that this issue has now been resolved > definitively, but in this OCO era only IBM can tell us that it has been.
Greg Dyck changed IEWFETCH to use ECKD in z/OS 1.7, which remedied the situation for fetching load modules from PDSes. He moved to DB2 Development several years ago, so I doubt that he follows IBM-MAIN any more. Jim Mulder z/OS System Test IBM Corp. Poughkeepsie, NY ---------------------------------------------------------------------- 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
