Source code for the availableProcessors

Question

Where can I find the soruce code/implementation for the availableProcessors() method in the java.lang.Runtime class.

most likely it's a native function. Are you interested in the C implementation? — John Dvorak, Oct 09 '13 at 06:29
Possible duplicate http://stackoverflow.com/questions/12594046/java-native-method-source-code @Abhilash you'll find your answer there — Alowaniak, Oct 09 '13 at 06:31
The method getAvailableProcessors is not part of Runtime class. — Juned Ahsan, Oct 09 '13 at 06:31
@Abhilash you probably meant `availableProcessors()` instead — Alowaniak, Oct 09 '13 at 06:33

score 3 · Answer 1 · answered Oct 09 '13 at 07:18

Look for os::_processor_count

The value is set in a OS-specific file. Here is the Linux version.

My strategy to find this was: Google for site:http://hg.openjdk.java.net/ jdk7 runtime

Then I opened the first link (http://hg.openjdk.java.net/jdk7/jdk7/hotspot/file/tip/src/share/vm/runtime/synchronizer.cpp) and removed the synchronizer.cpp from the URL. I can now see all the files in the runtime/ folder. Then I went through the file names. os.cpp sounded interesting.

For the link above, I replaced the revision number with tip to make the link always point to the latest version.

Inside of that file, I saw os::_processor_count.

Googling for that gave me a couple of links again. os_linux.cpp looked promising.

1 Answers1