Yifat, Without any other specification, such as BUFSP at define or BFND on the REPRO, IDCAMS without SMB used to default to BUFND of two, and only read one CI at a time.
Are you saying the default changed, or changed for Extended Format? I suggested it would not make huge difference for REPRO because the default CISZ for VSAM is 18K or 26K, and a large BUFND would not make a large difference in elapsed time on a small to medium size dataset. Ron > -----Original Message----- > From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of > Yifat Oren > Sent: Wednesday, September 15, 2010 4:05 AM > To: [email protected] > Subject: Re: [IBM-MAIN] DFSMS and System Managed Buffering > > Tobias, > > The reason you are not seeing the expected savings is that the IDCAMS REPRO > has already set and used the optimal number of data buffers regardless of > the DATACLAS change (so, no change has actually taken place; optimal > buffering was used for both before and after runs). > > You should see the savings when programs that are not taking care of their > VSAM buffering start using these data sets. > > I too think that 1MB is a bit constrictive for direct access LSR (bias=do) > buffering. > > Best Regards, > Yifat > > ---------------------------------------------------------------------- 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
