What is your MAXSYSTEMS value? There is a false lock contention penalty when your MAXSYSTEMS value exceeds 7 or 23. Of course your MAXSYSTEMS has to match the actual number of parallel sysplex members :) Also what is your false lock contention rate? 1% is typically acceptable though it really varies with your application structure. Ultimately it is an application design issue, and Db2/IMS do a much better job of concurrent data access.
On Wed, Jan 12, 2022 at 2:19 AM Crawford, Robert C. < [email protected]> wrote: > All, > > I can't reconcile RLS lock structure false lock contention between the > various SMS statistics records. > > According to the type 42 subtype 17 we have a lot of false contention > (field SMF42HCC). However, our type 42 subtypes 15 (storage class response > time) and 16 (dataset response time) false contention buckets are zero. > The only exception in the 16's and 17's are fields SMF42GUB and SMF42FUB > that record locks that hashed to the same entry, which I thought was the > definition of false contention. However, the statistics in those fields > are a little more than half than the false contention reported in the > subtype 15's. > > I have SMS dataset monitoring set up for both SMF and IGWDATA. > > We are feature level Z (don't ask) so all the statistics should be below > the line. > > Our lock structure is already 1G in size so I'd like to find the root > cause of the false contention before making it any bigger. > > Does anyone have some advice? > > Thanks. > > Robert Crawford > Mainframe Management > United Services Automobile Association > (210) 913-3822 > > "Moy glaz! YA ne dolzhen dobavlyat' v nego puding!" > - Tolstoy > Please send requests to mainframe management through our front door at > go/mfmfrontdoor< > https://onc.jira.usaacloud.com/secure/Dashboard.jspa?selectPageId=15466> > > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to [email protected] with the message: INFO IBM-MAIN > ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
