SAP Basis Tech Supports

Symptom
Recommended Settings for the IBM 1.4.2 JVM (J9) for upgrading SAP NetWeaver 2004 SP14 and above or NetWeaver 7.0 (2004s) SP6 and above on AIX.
Other terms
Java Virtual Machine, JDK, SDK, J9, XI, Enterprise Portal, OOM
Reason and Prerequisites
For SAP NetWeaver 2004 SP14 or above or NetWeaver 7.0 (2004s) SP6 and above the new IBM 1.4.2 Hybrid JVM with J9 technology will be used on AIX. See SAP note 1039948.
OS level:
AIX 5.2 + APAR IY84258
This APAR will be in 5200-08-CSP or newer.
AIX 5.3 + APAR IY83071
This APAR will be in 5300-04 SP3 or newer.
AIX 6.1 SP1
JCE unrestricted policy files:
New (latest) files are required with 1.4.2 SR12!
SAP NetWeaver minimum patch level to use SR13 and newer:
see SAP note 1306760.
General Java VM settings for J2EE 6.40/7.0:
see SAP note 723909.
Wily Introscope:
Wily Introscope agent with version 7.1 patch 1 and above (SAP note 1015184).
Solution
1.Make sure that you have installed the required SDK:
Prerequisite to install SR13 is the implementation of SAP note 1306760 (Introducing missing iiop functionality for IBM JDK 1.4.2 SR13).
You have to download the SDK 1.4.2 64-bit ServiceRelease 13 from the new download site “IBM Java for ISVs”:
https://www14.software.ibm.com/webapp/iwm/web/preLogin.do?lang=en_US&source=swg-ibmjavaisv
You need an IBM ID (developerWorks or PartnerWorld) to login. Theaccess keyfor the entitlement isAQ2QQK45DQ.
You can verify this requirement by running ‘java -fullversion’. The version and build information in the output text must be:
“J2RE 1.4.2 IBM AIX 5L for PowerPC (64 bit JVM) build caix64142-20090307 (SR13)”.
The version information (java -Xj9 -version) if you run the J9 technology (-Xj9) will show a slightly different version information:
“IBM J9 VM (build 2.3, J2RE 1.4.2 IBM J9 2.3 AIX ppc64-64 j9ap64142-20090310 (JIT enabled)”. This version information can be found in the log and trace files too.
After the SDK upgrade you have to install the “Unlimited Strength Jurisdiction Policy Files” manually again, because these are overwritten during the SDK upgrade (see SAP note 754699, 739043).
For SR12 and newer, new (the latest) JCE Policy Files are required!2.Prepare the system to run with J9 technology
To use the new J9 technology for all SAP related applications are running under the <SID>adm user account you have to add the following environment variable:
IBM_JAVA_OPTIONS=-Xj9
Please add the environment variable to the <SID>adm user environment in /home/<SID>adm/ to the file “.j2eeenv_<hostname>.csh”
setenv IBM_JAVA_OPTIONS “-Xj9″
If IBM_JAVA_OPTIONS is already set e.g.
setenv IBM_JAVA_OPTIONS “-Xmx256M”
replace it with:
setenv IBM_JAVA_OPTIONS “-Xmx256M -Xj9″
Add to the file “.j2eeenv_<hostname>.sh”
IBM_JAVA_OPTIONS=”-Xj9″; export IBM_JAVA_OPTIONS
If IBM_JAVA_OPTIONS is already set e.g.
IBM_JAVA_OPTIONS=”-Xmx256M”; export IBM_JAVA_OPTIONS
replace it with:
IBM_JAVA_OPTIONS=”-Xmx256M -Xj9″; export IBM_JAVA_OPTIONS
Logoff and login again with the <SID>adm user and check if the environment is set (env command).
During a NetWeaver 2004 upgrade the <SID>adm user environment will be overwritten by the SAP installer. So please double check the environment and add the -Xj9 parameter again.3.Prepare the J2EE to detect the new JDK
Delete the instance.properties.vmprop file in the /usr/sap/<SID>/<JCXX>|<DVEBMGSXX>/j2ee/cluster directory.
During the first J2EE startup this file will be recreated with the new JVM version information.4.Configure the J2EE (Dispatcher and Server) JVM parameter set
Start the configtool
(/usr/sap/<SID>/<JCXX>|<DVEBMGSXX>/j2ee/configtool/configtool.sh)
Do not remove any application specific parameters which starts with a “-D”, which are described in SAP note 723909.
Remove the previous JVM specific parameters like:
-Xloratio0.3
-Xparroot
-Xconcurrentlevel6
-Xconcurrentbackground4
-XSoftRefThreshold0
-Xconmeter2
-Xk17000
-Xp2048K,128K
-verbose:Xgccon
Set the following JVM parameters for the dispatcher:
Max heap size (in MB): 200
-Xms200M
-Xmn70M
-Xgcpolicy:gencon
-verbose:gc
-Xj9
-Xdump:system:events=systhrow,filter=java/lang/OutOfMemoryError,request=exclusive+prepwalk

Set the following JVM parameters for all server nodes:
Max heap size (in MB): 2048
-Xms2048M
-Xmn1000M
-Xgcpolicy:gencon
-verbose:gc
-Xj9
-Xdisableexplicitgc
-Djava.net.preferIPv4Stack=true
-Xdump:system:events=systhrow,filter=java/lang/OutOfMemoryError,request=exclusive+prepwalk
-Xsoftrefthreshold1
Please implement SAP note 905211 to avoid performance degradation (PCD) due to changed soft reference handling by the GC (-Xsoftrefthreshold0).
The parameter change from -Xsoftrefthreshold0 to -Xsoftrefthreshold1 is recommended for SR12 or newer. This parameter change will reduce the number of loaded classes/classloader. Main results are shorter class unloading times and reduced GC pause times. In addition there will be a significant native memory footprint reduction with SR12. This effect is covered in SR13 already.
The parameter-Djava.net.preferIPv4Stack=truecan avoid startup problemsin a network environment that is not configured to support IPv6. For more information see SAP note861333 and 1137949.
With the parameter -Xdump:system:events=systhrow,filter=java/lang/OutOfMemoryError,request=exclusive+prepwalk the JVM will write a system dump in case of an OOM. This can be used for the analysis with the Eclipse Memory Analyzer. For more information see SAP note 1259465.

Other settings:
For High Speed Debugging please consult note 862674 for detailed information. High speed debugging requires an updated startup framework or SP17 with NetWeaver 2004 or SP8 with NetWeaver 7.0 (2004s).