Re: Matching Java thread-ID to native Linux PID - Sun Java 1.5.x

From:

Nigel Wade <nmw-news@ion.le.ac.uk>

Newsgroups:

comp.lang.java.help

Date:

Mon, 22 Nov 2010 15:15:43 +0000

Message-ID:

<8kvfovFrriU1@mid.individual.net>

On 22/11/10 14:44, Federico Cozzi wrote:

On 22 Nov, 14:27, Nigel Wade <nmw-n...@ion.le.ac.uk> wrote:

ps -Lef
will show every LWP along with the associated PID and PPID.

This outputs only Process ID (and Parent Process ID), which is an OS-
level ID.

It outputs the PID, the PPID and the LWP id. The LWP id is what 'top -H'
shows in the PID field, which is what you need to map a thread to the
actual PID.

I need to correlate this output to Java Thread-ID, which is a JVM-
level ID (starts from 1 when the JVM is started) and is what most Java
tools use. Under Java a thread has both a thread-name and a thread-ID;
if the JVM uses native threads (like Sun Java 1.5 on Linux) each Java
Thread is mapped to a Linux LWP, but IDs are different.

It appears I misunderstood your post. I thought you wanted to identify
which Java process was running the the theads in question so you could
attach a Java debugger to the correct process. I'm sorry, I have no idea
how Java thread id's relate to the LWP id.

--
Nigel Wade