RFR 8199435 : Unsafe publication of java.util.Properties.map

[Claes Redestad]

On 2018-06-18 13:06, Peter Levart wrote:
>> Adding a volatile read on every read through Properties is likely to 
>> have some performance impact,
>
> On non-Intel architectures in particular. On intel it would just 
> inhibit some JIT optimizations like hoisting the read of field out of 
> loop... 

Right, and coincidentally those platforms are where I'd expect the 
current implementation to cause bugs (I've not been able to provoke
any real error on my Intel-based workstations).

I'd be surprised if we'd be much slower than pre-8029891 using volatiles 
(volatile read vs synchronized - even with biased locking),
and we'd still retain the scalability benefits of 8029891.

Ignore my remarks about clone - I'm just back from vacation and have 
apparently forgotten how cloning works. :-)

/Claes