Kbase P57432: How to use the Verbose Garbage Collection -verbosegc switch
| Autor |
Progress Software Corporation - Progress |
| Acesso |
Público |
| Publicação |
22/01/2010 |
|
Status: Verified
GOAL:
How to use the Verbose Garbage Collection -verbosegc switch
GOAL:
How to determine information about Java performance tuning
GOAL:
How to troubleshoot java memory problems
GOAL:
How to troubleshoot performance-related problems in Java
GOAL:
Use of the -verbosegc Option
FACT(s) (Environment):
All Supported Operating Systems
Progress 9.x
OpenEdge 10.x
FIX:
Garbage collection uses a scheduling algorithm to automatically release memory from java applications.
When garbage collection occurs, all user threads are stopped and states are saved. After the garbage collection ends, all threads are started backup. This start-stop time becomes expensive, and it must be minimized in order to maximize total work done.
The -verbosegc command prints a message when Java garbage collection occurs. The output is used to analyze whether or not the application is getting work done effectively, or is thrashing while it is in garbage collection mode. Verbosegc will display the time in milliseconds since the last collection. This switch can be seen as an option to the JRE if you use the -option flag on the command line.
The output of -verbosegc is written to the stdout or stderr of the broker process.
In releases prior to Progress 9.1D, this is logged in the AdminServerSystemOut.log file
In the Progress 9.1D release, this is always logged in the admserv.log file until 9.1D05 service pack.
In Progress 9.1D05 and all later releases, this is logged in the admserv.log file if the logging level is set to 4 or higher. This is done by including the -DLogLevel=4 option for the JRE.
The switch can be activated as follows in the ubroker.properties file:
For releases up to Progress 9.1D05:
[UBroker.AS.sometest]
jvmArgs=-verbosegc
For releases starting with Progress 9.1D05:
[UBroker.AS.sometest]
jvmArgs=-verbosegc,-DLogLevel=4