Jeffrey, The "NEXT" path selection algorithm uses a type of round robin technique - there is no "first path," just the "next path".
Please don't tell me someone from HDS recommended this. There are some low order preference affects of NEXT, but it would hardly make enough of a difference to worry about. And with FICON - well the concept of path busy is an entirely different animal. Ron > -----Original Message----- > From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] On > Behalf Of Jeffrey Deaver > Sent: Thursday, 13 July 2006 2:17 AM > To: [email protected] > Subject: Path Round Robin? > > I have a vendor telling me that I should round-robin the paths on my > control unit add statements. Something about that it provides a > different > first path for each control unit which can improve performance. > > Like this... > cunumbr=0,path=(0,1,2,3,4,5) > cunumbr=1,path=(1,2,3,4,5,0) > cunumbr=2,path=(2,3,4,5,0,1) > cunumbr=3,path=(3,4,5,0,1,2) > cunumbr=4,path=(4,5,0,1,2,3) > > instead of simply like this.... > cunumbr=0,path=(0,1,2,3,4,5) > cunumbr=1,path=(0,1,2,3,4,5) > cunumbr=2,path=(0,1,2,3,4,5) > cunumbr=3,path=(0,1,2,3,4,5) > cunumbr=4,path=(0,1,2,3,4,5) > > Actually, he wasn't sure about it, but said he had others that swore by it > and so figured it couldn't hurt. Personally I think it makes it harder > to read, but if there is actually a performance benefit... > > Anyone know if there is any truth to this? Or if it used to be true but > no > longer applies? We've never done the round-robin thing. > > Jeffrey Deaver, Senior Analyst, Systems Engineering > 651-665-4231 > > ---------------------------------------------------------------------- > 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 ---------------------------------------------------------------------- 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
