Codereview request: 6980984 java/lang/management/MemoryMXBean/MemoryManagement is not robust when getMax() returns -1

[Daniel Fuchs]

Hi Shanliang,

I just notice that there are some synchronization
issues in the test as well: all static variables
used by the allocator thread should be declared
volatile (chunkSize, mpool ...).

-- daniel

On 1/22/14 2:27 PM, shanliang wrote:
> Hi,
>
> The bug was reproduced only on jdk6 on my Mac, but well passed on 7/8/9.
>
> We can have several solutions, like to use:
>     Runtime.getRuntime().maxMemory()
>     Runtime.getRuntime().totalMemory;
>
>     MemoryUsage.getCommitted()
>
> or hard-code chunkSize to be 1M.
>
> I found that the test ran much faster with:
>     chunkSize = Runtime.getRuntime().freeMemory()/10;
> than:
>     chunkSize = 1M;
>
> webrev:
> http://cr.openjdk.java.net/~sjiang/JDK-6980984/00/
>
> bug:
> https://bugs.openjdk.java.net/browse/JDK-6980984
>
> Thanks,
> Shanliang