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Bug ID: JDK-5086475 Ctrl-break handler should print the java.util.concurrent locks info
JDK-5086475 : Ctrl-break handler should print the java.util.concurrent locks info

Details
Type:
Enhancement
Submit Date:
2004-08-12
Status:
Resolved
Updated Date:
2005-06-14
Project Name:
JDK
Resolved Date:
2005-06-14
Component:
core-svc
OS:
generic
Sub-Component:
tools
CPU:
generic
Priority:
P4
Resolution:
Fixed
Affected Versions:
5.0
Fixed Versions:

Related Reports
Relates:

Sub Tasks

Description
The java.util.concurrent locks are not known to the VM. Ctrl-break
handler and M&M API only provide lock information for the object
monitors but not Java-level JSR-166 primitives.

The dumping mechanism should be enhanced to include the JSR-166
locks information.

See comments in 5086470 for the email thread about this request.

                                    

Comments
EVALUATION

Will consider this in Mustang.

###@###.### 2004-08-12

The control-break (Windows) and SIGQUIT output are improved:
1. to print out the java.util.concurrent.locks lock that a thread is blocked on (i.e. the object responsible for the thread parking).
2. to find deadlocks involving both object monitors and java.util.concurrent locks.
3. to print out the list of all java.util.concurrent.locks owned by each thread if -XX:+PrintConcurrentLocks is set.
4. to print out the java.lang.Thread.State a thread is at.

Note that VM will only provide this monitoring and diagnostic support for any synchronizers that use AbstractOwnableSynchronizer to implement its synchronization mechanism.  A customized synchronizer (user-defined ones) that does not set the exclusive owner when granting a lock to thread and does not set the object responsible for the thread parking at contention time will have no information printed in the control-break/SIGQUIT output.

See 5086470 for details.
###@###.### 2005-05-20 23:18:56 GMT
                                     
2005-05-20
SUGGESTED FIX

See 5086470.
###@###.### 2005-05-20 23:18:56 GMT
                                     
2005-05-20



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