Support Forums: Message List - Fixing the Java Memory Model

Mutable Immutable Fields

Mon, 01 Mar 2004 16:40:03 -0500

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double check

Mon, 01 Mar 2004 13:19:28 -0500

In a multi-processor machine, the use of a volatile in the new memory model is still going to be significantly faster than the use of a synchronized block. The critical issue is that processors won't have to vie for the lock, which is a particularly...

cache coherency

Mon, 01 Mar 2004 13:07:10 -0500

Doug: It's natural that in some hardware architectures, a processor may choose to bring in a full page of memory into it's CPU cache rather than caching on an object by object basis. In an situation like this, it could be possible to cache stale data...

double check

Mon, 01 Mar 2004 11:15:16 -0500
In the new JMM double-checked locking does work if you make "x" volatile. However, the rules of the new JMM effectively force the VM to flush it's cache when accessing a volatile field, so it becomes almost as expensive as using synchronized...

Mutable Immutable Fields

Mon, 01 Mar 2004 00:43:29 -0500
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monitorenter, Fixing the Java Memory Model

Sun, 29 Feb 2004 22:27:25 -0500

From the quick look I had at the new spec, it seems that the spec ensures the following: assuming the object is "properly constructed" in the sense that the constructor does not "leak out" references to the...

double check

Sun, 29 Feb 2004 21:35:48 -0500

By double check I mean:
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Mutable Immutable Fields

Sun, 29 Feb 2004 21:20:18 -0500
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Fixing the Java Memory Model

Sun, 29 Feb 2004 19:21:55 -0500

This may be a dumb question, but...
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Mutable Immutable Fields

Sun, 29 Feb 2004 19:12:10 -0500
The article points out that in the older Java Memory Models, other threads might see a "half-constructed" object under certain race conditions. If I'm reading this right, the following code could also break?...

double check

Sun, 29 Feb 2004 10:47:26 -0500
No, double-checked locking does not work in either of the JMMs. In the new JMM double-checked locking does work if you make "x" volatile. However, the rules of the new JMM effectively force the VM to flush it's cache when accessing a volatile...

double check

Sun, 29 Feb 2004 00:36:29 -0500
Does anybody know if double check works with the JDK 1.4 JMM or JDK 1.5 JMM?...

Fixing the Java Memory Model

Sat, 28 Feb 2004 11:06:40 -0500
Hi Brian,...

monitorenter, Fixing the Java Memory Model

Fri, 27 Feb 2004 17:56:00 -0500
From the quick look I had at the new spec, it seems that the spec ensures the following: assuming the object is "properly constructed" in the sense that the constructor does not "leak out" references to the instance being...

Fixing the Java Memory Model

Fri, 27 Feb 2004 15:31:57 -0500

The thread's "cache" is just a logical indirection designed to allow VMs not to perform every memory action directly to the main memory.
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