I might look at using binary counters instead of packed... Initialization then is trivial; incrementing a counter might be ugly depending on how large a binary counter you need (full word? double word?)
If you must use packed, how about mass smash to zero and then loop thru OI or MVI rightmost byte of counters with X'0C' All of this speculation assumes the counters can't just be assembled with appropriate DC statements?? Kerry Liles On Sat, Nov 29, 2025, 10:35 p.m. Brian Westerman < [email protected]> wrote: > Hi, > > I have a program in which I have 104 PL4 fields tht are used for various > counters, and when the program starts it spends a significant amount of > time initializing all of those fields to zero. > > we used to use ZAP field,=PL4'0' and then I found an entry (on the web) > that said it would be "slightly" faster to use MVC, so I changed it to 104 > MVC filed,=PL4'0'. > > Is there not a quicker way to do this? I know that I can ripple the first > byte of a field for up to 256 bytes with a single instruction, but can that > same type of thing be done with a 4 byte packed field? > > If not, is there a quicker way to initialize these fields without doing > each one separately? > > Thanks for any tips. > > Brian >
