RFR(S): 8058897 - Unsafe.reallocateMemory() ignores -XX:MallocMaxTestWords setting.

David Holmes david.holmes at oracle.com
Wed Jan 7 01:46:28 UTC 2015


Hi Christian,

On 7/01/2015 10:12 AM, Christian Tornqvist wrote:
> Hi everyone,
>
> This change makes realloc use MallocMaxTestWords, a debug option used to
> simulate malloc OOM.

diagnostic not debug. :)

> Webrev:
>
> http://cr.openjdk.java.net/~ctornqvi/webrev/8058897/webrev.00/

As this is diagnostic this may not matter much but you now update the 
counter before doing the actual malloc/realloc. I don't know how this 
gets used in practice so don't know if it might impact anything.

Nit - the test may have a bug:

58         try {
59             unsafe.reallocateMemory(address, 20 * 1000 * 1000 * 8);
60             throw new RuntimeException("Did not get expected OOM");

You might get OOM from the "throw new ..." rather than the reallocate. :)

But for what this is this seems fine. :)

David

>
>
> Bug:
>
> https://bugs.openjdk.java.net/browse/JDK-8058897
>
>
>
> Thanks,
>
> Christian
>


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