Determine virtual storage to be backed. Virtual to real (for that LPAR) no greater than 3:1. This can be done by estimation or looking at RMF. Allocate sufficient local page slots such that no single local page DS has more than 30% of slots in use. Spread these slots over and many devices/paths as practical.
Beware of paging hotspots (Directed VIO,......) and spikes (SVC dumps,....) HTH, <snip> Hope everyone had a good holiday. Just looking at doing a little housecleaning. Haven't visited Local page dataset's since 2006. In general we don't page much, and if we do it usually because there is a problem, or someone is doing something they probably shouldn't. MVS Init and Tuning Guide gives some pointers, but was hoping for some real life ROT's to follow. Today we have a roughly 36GB of LOCAL page for each system, that was setup in 2006 spread across 4 mod-9's. Back then we didn't have the amount of memory on the processors that we have now, nor did we have DB2's using data above the bar. Most of the systems in our sysplex have around 40Gb of memory configured online. We have many more DB2 V10 instances active now than we did in 2006. Without doing a lot of math and measurements, I'm leaning towards giving each system between 80 and 100Gb's of local page spread across 4 LOCAL page datasets for each system? We have dynamic PAV's enabled. That would be 3-4 mod27's each. I could go with mod-54's, at 2 per system, but not really sure how much the actual number of virtual DASD devices even matters anymore? </snip> ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
