|
Let's try that again with the attachement... Resending and including the Runtime team since I think that team owns deadlock detection support at this point... Dan -------- Original Message --------
Hi folks, I notice that when you send a sigquit to a VM, and threads are deadlocked in class initialization, then the thread state is reported as RUNNABLE. Is this deliberate?
With the attached program (which mostly deadlocks on clinit - I don't
have the time to remember how to write the
100-percent-will-always-deadlock version today), here is the output
from JDK7 b74.
2009-11-17 15:41:14
Full thread dump OpenJDK Server VM (17.0-b03 mixed mode):
"DestroyJavaVM" prio=10 tid=0xaf519c00 nid=0x2221 waiting on condition
[0x00000000]
java.lang.Thread.State: RUNNABLE
"Thread-1" prio=10 tid=0xaf518000 nid=0x2230 in Object.wait() [0xaf3db000]
java.lang.Thread.State: RUNNABLE
at NPE$2.run(NPE.java:60)
at java.lang.Thread.run(Thread.java:717)
"Thread-0" prio=10 tid=0xaf516800 nid=0x222f in Object.wait() [0xaf42c000]
java.lang.Thread.State: RUNNABLE
at Base.<clinit>(NPE.java:33)
at NPE$1.run(NPE.java:54)
at java.lang.Thread.run(Thread.java:717)
"Low Memory Detector" daemon prio=10 tid=0xaf500c00 nid=0x222d
runnable [0x00000000]
java.lang.Thread.State: RUNNABLE
"CompilerThread1" daemon prio=10 tid=0x08109c00 nid=0x222c waiting on
condition [0x00000000]
java.lang.Thread.State: RUNNABLE
"CompilerThread0" daemon prio=10 tid=0x08107800 nid=0x222b waiting on
condition [0x00000000]
java.lang.Thread.State: RUNNABLE
"Signal Dispatcher" daemon prio=10 tid=0x08105c00 nid=0x222a waiting
on condition [0x00000000]
java.lang.Thread.State: RUNNABLE
"Finalizer" daemon prio=10 tid=0x080f6c00 nid=0x2229 in Object.wait()
[0xaf821000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
- waiting on <0xecf30bd0> (a java.lang.ref.ReferenceQueue$Lock)
at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:135)
- locked <0xecf30bd0> (a java.lang.ref.ReferenceQueue$Lock)
at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:151)
at java.lang.ref.Finalizer$FinalizerThread.run(Finalizer.java:177)
"Reference Handler" daemon prio=10 tid=0x080f2000 nid=0x2228 in
Object.wait() [0xaf872000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
- waiting on <0xecf30990> (a java.lang.ref.Reference$Lock)
at java.lang.Object.wait(Object.java:502)
at java.lang.ref.Reference$ReferenceHandler.run(Reference.java:133)
- locked <0xecf30990> (a java.lang.ref.Reference$Lock)
"VM Thread" prio=10 tid=0x080ed400 nid=0x2227 runnable
"GC task thread#0 (ParallelGC)" prio=10 tid=0x08057400 nid=0x2222 runnable
"GC task thread#1 (ParallelGC)" prio=10 tid=0x08058c00 nid=0x2223 runnable
"GC task thread#2 (ParallelGC)" prio=10 tid=0x0805a000 nid=0x2224 runnable
"GC task thread#3 (ParallelGC)" prio=10 tid=0x0805b800 nid=0x2225 runnable
"VM Periodic Task Thread" prio=10 tid=0xaf502c00 nid=0x222e waiting on
condition
JNI global references: 643
Heap
PSYoungGen total 12480K, used 860K [0xecf30000, 0xedd10000, 0xf40f0000)
eden space 10752K, 8% used [0xecf30000,0xed007148,0xed9b0000)
from space 1728K, 0% used [0xedb60000,0xedb60000,0xedd10000)
to space 1728K, 0% used [0xed9b0000,0xed9b0000,0xedb60000)
PSOldGen total 113792K, used 0K [0xb40f0000, 0xbb010000, 0xecf30000)
object space 113792K, 0% used [0xb40f0000,0xb40f0000,0xbb010000)
PSPermGen total 16384K, used 1764K [0xb00f0000, 0xb10f0000, 0xb40f0000)
object space 16384K, 10% used [0xb00f0000,0xb02a91d0,0xb10f0000)
|
import java.util.*;
import java.util.concurrent.*;
import java.security.SecureRandom;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.lang.management.ManagementFactory;
import java.util.concurrent.*;
import java.util.concurrent.locks.*;
import java.net.*;
import java.lang.reflect.Field;
import javax.management.*;
import java.lang.management.*;
import javax.script.*;
import java.io.*;
import java.util.Random;
import java.security.SecureRandom;
abstract class Base {
static DerivedA a;
static DerivedB b;
static {
a = new DerivedA();
Thread.yield();
while (NPE.proceed != 2);
b = new DerivedB();
}
}
class DerivedA extends Base {
}
class DerivedB extends Base {
}
public class NPE {
public static volatile int proceed = 0;
static DerivedA a;
static DerivedB b;
public static void main(String[] args) {
new Thread(new Runnable() {
public void run() {
proceed ++;
a = new DerivedA();
}
}).start();
new Thread(new Runnable() {
public void run() {
proceed ++;
b = new DerivedB();
}
}).start();
}
}
