hang in Lion

[Michael McMahon]

I was able to repeat it using java version "1.6.0_27"
on an imac (with -Xcomp, but not -Xint) .

Was not able to repeat using 7 on the same system,
I also couldn't repeat it on a different machine using 1.6.0_29.

So, maybe the issue was fixed between updates 27 and 29?

- Michael.

On 30/11/11 14:21, Henri Gomez wrote:
> Hi Charles
>
> Just tried with latest build of OpenJDK 7 for OSX
> (http://openjdk-osx-build.googlecode.com/files/OpenJDK-OSX-1.7-universal-jdk-b219-20111130.dmg)
> :
>
> openjdk version "1.7.0-b219"
> OpenJDK Runtime Environment (build 1.7.0-b219-20111130)
> OpenJDK 64-Bit Server VM (build 21.0-b17, mixed mode)
>
> Compiled and run with OpenJDK 7 :
>
> Started
> Awaiting complete...
> Thread started Thread-0
> Thread started Thread-1
> Thread-0: 10000
> Thread-1: 20000
> Thread-0: 30000
> Thread-0: 40000
> Thread-1: 50000
> Thread-1: 60000
> Thread-1: 70000
> Thread-1: 80000
> Thread-1: 90000
> Thread-1: 100000
> Thread-0: 110000
> Thread-0: 120000
> Thread-1: 130000
> Thread-0: 140000
> Thread-1: 150000
> Thread-0: 160000
> Thread-0: 170000
> Thread-0: 180000
> Thread done Thread-1
> Thread-0: 190000
> Thread-0: 200000
> Thread done Thread-0
> Completed...
>
> Tried on latest Apple Java 6 (1.6.0-29) and rebuilt Foo with it :
>
> java version "1.6.0_29"
> Java(TM) SE Runtime Environment (build 1.6.0_29-b11-402-10M3527)
> Java HotSpot(TM) 64-Bit Server VM (build 20.4-b02-402, mixed mode)
>
> Started
> Thread started Thread-1
> Thread started Thread-2
> Awaiting complete...
> Thread-2: 10000
> Thread-1: 20000
> Thread-1: 30000
> Thread-2: 40000
> Thread-2: 50000
> Thread-1: 60000
> Thread-1: 70000
> Thread-2: 80000
> Thread-2: 90000
> Thread-1: 100000
> Thread-1: 110000
> Thread-2: 120000
> Thread-1: 130000
> Thread-1: 140000
> Thread-1: 150000
> Thread-1: 160000
> Thread-1: 170000
> Thread-2: 180000
> Thread-2: 190000
> Thread-1: 200000
> Thread done Thread-2
> Thread done Thread-1
> Completed...
>
> Tried on both SnowLeopard and Lion machines.
>
> Cheers
>
> 2011/11/30 Charles K Pepperdine<kirk at kodewerk.com>:
>> Hi,
>>
>> I've got a chunk of code that mysteriously hangs on my new i7 Air running Lion. This code was given to me by a friend that is also running Lion. We've given it to another person that is also running Lion. I'm using 1.6.0_26-b02-383. It doesn't hang all the time and it doesn't hang on my older i7 17" MBP running Snow Leopard. It's also been tested on other MBP's running Snow Leopard without hanging. Forcing a core dump after the hang gave us this.
>>
>>> Thread 24:  Java: Thread-1
>>> 0   libSystem.B.dylib                 0x00007fff89f88d7a mach_msg_trap + 10
>>> 1   libSystem.B.dylib                 0x00007fff89f893ed mach_msg + 59
>>> 2   libclient64.dylib                 0x000000010100d903 jio_snprintf + 37641
>>> 3   libclient64.dylib                 0x000000010100d7c3 jio_snprintf + 37321
>>> 4   libclient64.dylib                 0x000000010100d722 jio_snprintf + 37160
>>> 5   libclient64.dylib                 0x000000010100c5ad jio_snprintf + 32691
>>> 6   libclient64.dylib                 0x000000010100c4ef jio_snprintf + 32501
>>> 7   libclient64.dylib                 0x00000001011afefd JVM_GetClassInterfaces + 12075
>>> 8   libclient64.dylib                 0x00000001010a7c8c JVM_Lseek + 204251
>>> 9   libclient64.dylib                 0x00000001010a7bea JVM_Lseek + 204089
>>> 10  libclient64.dylib                 0x00000001011b4931 JVM_Socket + 5319
>>> 11  ???                               0x000000010380f0e7 0 + 4353749223
>>> 12  ???                               0x000000010386fd90 0 + 4354145680
>>>
>>> Thread 25:  Java: Thread-2
>>> 0   libSystem.B.dylib                 0x00007fff89f88d7a mach_msg_trap + 10
>>> 1   libSystem.B.dylib                 0x00007fff89f893ed mach_msg + 59
>>> 2   libclient64.dylib                 0x000000010100db03 jio_snprintf + 38153
>>> 3   libclient64.dylib                 0x00000001010cb569 JVM_Write + 9130
>>> 4   libclient64.dylib                 0x00000001011ddfcd JVM_NanoTime + 39179
>>> 5   ???                               0x000000010386ea60 0 + 4354140768
>> All of the other thread could be attributed to VM processes (GC, compiler etc...).
>>
>> On my machine, the hang seems to only happen when thread-2 finishes before thread-1. I've never seen it hang when thread-1 finishes before thread-2 Again it doesn't hang all the time when thread-2 finishes first. This is a hard hang in that I can only get rid of the process with a kill -9. ^C and kill simply don't to anything.
>>
>> Code follows,
>>
>> Regards,
>> Kirk Pepperdine
>>
>> public class Foo {
>>
>>     private int counter;
>>
>>     public static void main(String[] args) throws Exception {
>>         new Foo().run();
>>     }
>>
>>     public void run() throws Exception {
>>
>>         Thread[] threads = new Thread[2];
>>
>>         for (int i = 0; i<  threads.length; i++) {
>>             threads[i] = new Thread() {
>>                 public void run() {
>>
>>                     System.out.println("Thread started " + Thread.currentThread().getName());
>>                     System.out.flush();
>>
>>                     for (int i = 0; i<  100000; i++) {
>>                         increment();
>>                     }
>>
>>                     System.out.println("Thread done " + Thread.currentThread().getName());
>>                     System.out.flush();
>>                 }
>>             };
>>         }
>>
>>         for (Thread t : threads) {
>>             t.start();
>>         }
>>
>>         System.out.println("Started");
>>         System.out.flush();
>>
>>         System.out.println("Awaiting complete...");
>>         System.out.flush();
>>
>>         for (Thread t : threads) {
>>             t.join();
>>         }
>>
>>         System.out.println("Completed...");
>>         System.out.flush();
>>     }
>>
>>     private synchronized void increment() {
>>
>>         counter++;
>>
>>         if (counter % 10000 == 0) {
>>             System.out.printf("%s: %d\n", Thread.currentThread().getName(), counter);
>>             System.out.flush();
>>         }
>>     }
>> }