?
Solved

What is the standard Java Garbage Collection method for Red Hat 6.x

Posted on 2014-12-31
4
Medium Priority
?
316 Views
Last Modified: 2015-01-05
I installed Red hat 6.x, including the default Java that comes with the system

What is the default Garbage Collection method used by this version of Java

How can I double check ?

Thanks
0
Comment
Question by:Anthony Lucia
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 2
  • 2
4 Comments
 
LVL 28

Assisted Solution

by:dpearson
dpearson earned 1000 total points
ID: 40526138
In part it depends on whether you're running 32-bit or 64-bit.

This table should help you figure it out:
http://www.techpaste.com/2012/02/20/default-jvm-settings-gc-jit-java-heap-sizes-xms-xmx-operating-systems/#more-3569

Or here:
http://www.fasterj.com/articles/oraclecollectors1.shtml

I'm not aware of any simple way to print it out at the command line.  The first page suggests using
 java -XX:+PrintCommandLineFlags -version
but I think that will only help if RedHat is overriding the default.  Still it may be useful.

Hope that helps,

Doug
0
 
LVL 62

Assisted Solution

by:gheist
gheist earned 1000 total points
ID: 40526515
OpenJDK 6 is more or less a rebuild of open-sourced JDK
So it is safe to assume it is a Hotspot Server VM with G1 garbage collector.
0
 
LVL 28

Accepted Solution

by:
dpearson earned 1000 total points
ID: 40526784
Unless OpenJDK is working with a different version system I don't think G1 is the default in OpenJDK 6.

According to this G1 only came in fully with JDK7u4:
http://www.oracle.com/technetwork/tutorials/tutorials-1876574.html
The G1 garbage collector is fully supported in Oracle JDK 7 update 4 and later releases

Even in JDK7 it doesn't default to G1 (at least our CentOS Linux installs) - it's just an available option.
0
 
LVL 62

Assisted Solution

by:gheist
gheist earned 1000 total points
ID: 40526790
Oh sorry it was called "parallel newgen" for java 1.6
Default is determined on startup. It could be one or other depending on heap size anc CPU number in system.

The "default java" that comes with system is gcj 1.4.2 that uses Boehm GC
0

Featured Post

Get free NFR key for Veeam Availability Suite 9.5

Veeam is happy to provide a free NFR license (1 year, 2 sockets) to all certified IT Pros. The license allows for the non-production use of Veeam Availability Suite v9.5 in your home lab, without any feature limitations. It works for both VMware and Hyper-V environments

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Linux users are sometimes dumbfounded by the severe lack of documentation on a topic. Sometimes, the documentation is copious, but other times, you end up with some obscure "it varies depending on your distribution" over and over when searching for …
Basic understanding on "OO- Object Orientation" is needed for designing a logical solution to solve a problem. Basic OOAD is a prerequisite for a coder to ensure that they follow the basic design of OO. This would help developers to understand the b…
Viewers learn how to read error messages and identify possible mistakes that could cause hours of frustration. Coding is as much about debugging your code as it is about writing it. Define Error Message: Line Numbers: Type of Error: Break Down…
Viewers will learn about basic arrays, how to declare them, and how to use them. Introduction and definition: Declare an array and cover the syntax of declaring them: Initialize every index in the created array: Example/Features of a basic arr…
Suggested Courses
Course of the Month14 days, 3 hours left to enroll

800 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question