Debugging Just In Time compiler failures on Windows for versions 5.0 and 5.1
 Technote (troubleshooting)
 
Problem(Abstract)
When trying to determine the nature of a Just In Time (JIT) failure on Windows®, use the attached script to start IBM® WebSphere® Application Server.
 
Cause
Failure converting Java™ bytecode to machine code resulting in a Application Server failure.
 
Resolving the problem
To debug JIT failures, run multiple tests and gather log files from each test.
  1. Copy the attached startJit50.bat file to WebSphere-root\bin (c:\WebSphere\AppServer\bin)


  2. Modify the startJit50.bat file with the following changes:
    • Determine what Application Server you are debugging, then modify the script. The script is set to debug server1.
    • Create the following directory: c:\JitDebug or modify the script to reflect another location.


  3. To run the script from a command prompt, enter the script name and an option (1-thru-4). For example, c:\WebSphere\AppServer\bin\startJit50.bat 1 > test1.log 2>&1
    Option
    Optimization
    Definition
    1
    NMMI2JIT
    Disables in method transfer
    2
    NINLINING
    Disables method Inlining
    3
    NQOPTIMIZE
    Disables quadruple optimization
    4
    NALL
    Disables optimization but not compilation
  4. Failure occurs, restart the test and select the next option.


  5. Send the following files to IBM Support after all of the tests are complete:
    • All files from c:\JitDebug
    • stderr and stdout files from the Application Server
 
startjit50.bat
 
Cross Reference information
Segment Product Component Platform Version Edition
Application Servers Runtimes for Java Technology Java SDK
 
 


Document Information


Product categories: Software > Application Servers > Distributed Application & Web Servers > WebSphere Application Server > Java SDK
Operating system(s): Windows
Software version: 5.1
Software edition:
Reference #: 1164080
IBM Group: Software Group
Modified date: Oct 23, 2007