How does volatile actually work?

Posted by FredOverflow on Stack Overflow See other posts from Stack Overflow or by FredOverflow
Published on 2010-04-22T20:58:44Z Indexed on 2010/04/23 14:53 UTC
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java

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volatile

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concurrency

Marking a variable as volatile in Java ensures that every thread sees the value that was last written to it instead of some stale value. I was wondering how this is actually achieved. Does the JVM emit special instructions that flush the CPU cashes or something?

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