Gary, For the JVM to be using that much CPU just for a simple HelloWorld, I'd guess you have an unsuitable LE STACK option. The JVM is an XPLinked system, and so uses a downward-growing stack. LE detects when the stack should be extended because a 0C4 results from trying to save registers in the guard page. This is a pretty big overhead when it happens frequently. Check your LE STACK runtime option. CICS recommends
STACK(128K,128K,ANY,KEEP,128K,128K) You will also probably want to investigate heap usage. Running with RPTSTG(ON) will provide you with storage usage reports when the JVM terminates. (Don't run with this on in production, though) Tom Grieve CICS Development IBM Hursley Park On Mon, 17 Sep 2007 11:00:59 -0400, Gary Green <[EMAIL PROTECTED]> wrote: >Does anyone have any tuning/performance references/links for Java under z/OS? > >Some tentative footsteps were taken to develop Java apps to run under USS and the "Hello World" app sucked down 30% of the CPU during the time the app was running. :( So, I gotta prepare for the onslaught when things really kick into high gear. > >Thanks. > >---------------------------------------------------------------------- >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
