Archive for Memory

Java memory management

Posted in Java with tags , on November 17, 2006 by wsjoung

JVM with the -verbose:gc or -Xloggc:
a diagnostic message is printed on the console or to a log file every time the GC runs, including how long it took, the current heap usage, and how much memory was recovered. Logging GC usage is not intrusive, and so it is reasonable to enable GC logging in production by default in the event you ever need to analyze memory problems or tune the garbage collector.

JVM with the -Xrunhprof[:suboption=value]
Enables cpu, heap, or monitor profiling.
java -Xrunhprof:help to obtain a list of suboptions and their default values.

GC Portal
The GC Portal enables analysis and performance tuning of Java applications from a garbage collection (GC) perspective by mining the verbose:gc logs generated by the JVM.

HPjtune is a Java Garbage Collection visualization tool for analyzing garbage collection activity in a Java program. The analysis is carried out off-line or on-line, based on the output of the JVM via the -Xloggc or -Xverbosegc output file.

JavaTM HotSpot VM Options