Review request: 8024650: Don't adjust MaxMetaspaceSize up to MetaspaceSize

[Jon Masamitsu]

To follow up on Thomas' point about

   90   if (MetaspaceSize < 256*K) {
   91     vm_exit_during_initialization("Too small initial Metaspace size");
   92   }

There really isn't a value of MetaspaceSize that is too small.  It is just
a high-water-mark.  If it was zero, it should still work (just would get
a GC  sooner rather than later).  I haven't tried it (hit the
assertion) but it should work.  I'll file a bug if you don't want to include
it with this.

Jon


On 9/13/2013 4:55 AM, Stefan Karlsson wrote:
> http://cr.openjdk.java.net/~stefank/8024650/webrev.01/
>
> Changed in this revision:
> - Removed incorrect FLAG_IS_DEFAULT check
> - Added MetaspaceSize <= MaxMetaspaceSize assert
> - Added boundary test cases where MetaspaceSize and MaxMetaspaceSize 
> is set to 0.
> - Added rudimentary tests for the new firstMatch function.
>
> Rejected proposals:
> - Use MXBeans to get flag values.
> - Use WBApi to get conservative max heap alignment.
>
> thanks,
> StefanK
>
>
> On 09/12/2013 05:18 PM, Stefan Karlsson wrote:
>> http://cr.openjdk.java.net/~stefank/8024650/webrev.00/
>>
>> - Limit MetaspaceSize to MaxMetaspaceSize
>> - Make sure we don't align down to 0.
>> - jtreg test
>>
>> Note that this patch also adds/changes some functionality in the 
>> OutputAnalyzer in test/testlibrary.
>>
>> thanks,
>> StefanK
>