Review request for JDK-8011095 PropertyHashMap.rehash() does not grow enough

[Hannes Wallnoefer]

There must have been something wrong with your tests. I just pulled in 
your changes and I'm seeing abysmal performance on some octane 
benchmarks, and box2d is failing with a TypeError. All this goes away if 
I comment out the !properties.isEmpty() checks in addToHistory() and 
addToProtoHistory().

Hannes

Am 2013-03-31 13:16, schrieb Jim Laskey (Oracle):
> I well tested.  Beginning to believe that history in general may not be worth it, since it does take up considerable space and is somewhat compensated by predefined maps at set call sites.
>
>
> On 2013-03-31, at 5:08 AM, Marcus Lagergren <marcus.lagergren at oracle.com> wrote:
>
>> What Hannes said. Also looks good. Pls do some performance verification.
>> /M
>>
>> On Mar 30, 2013, at 4:40 PM, Hannes Wallnoefer <hannes.wallnoefer at oracle.com> wrote:
>>
>>> Looks good to me. The one thing I'm not sure about is the implications of not caching history for empty properties. On the one hand it seems plausible to avoid creating a huge property map tree where nothing is ever garbage collected, but on the hand everything starting at the empty properties map will not use history while still recording it, which is a wasted effort.
>>>
>>> I think we should do some testing with octane to see what operations actually use history or not with this scheme.
>>>
>>> Hannes
>>>
>>>
>>> Am 2013-03-30 14:53, schrieb Jim Laskey (Oracle):
>>>> Please review http://cr.openjdk.java.net/~jlaskey/8011095/webrev.00/
>>>>