On Mon, 17 Sep 2007 11:00:59 -0400, Gary Green <[EMAIL PROTECTED] SYSTEMS.COM> 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. > One thing you can do with a relatively short running Java jobs is to use the - Xquickstart argument: -Xquickstart Used for improving startup time of some Java applications. -Xquickstart causes the JIT to run with a subset of optimizations; that is, a quick compile. This quick compile allows for improved startup time. -Xquickstart is appropriate for shorter running applications, especially those where execution time is not concentrated into a small number of methods. -Xquickstart can degrade performance if it is used on longer-running applications that contain hot methods. The implementation of -Xquickstart is subject to change in future releases. java -Xquickstart HelloWorld Refer to the Java InfoCenters depending upon your version: Java 1.4.2 - http://publib.boulder.ibm.com/infocenter/javasdk/v1r4m2/index.jsp Java 5 - http://publib.boulder.ibm.com/infocenter/javasdk/v5r0/index.jsp And the Java for z/OS home page: http://www.ibm.com/servers/eserver/zseries/software/java/ I suppose if you are using JZOS, then you would add the -Xquickstart switch to the IBM_JAVA_OPTIONS variable. Aaron ---------------------------------------------------------------------- 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
