RFC: Experiment in accessing/managing persistent memory from Java

[Andrew Haley]

On 06/12/2018 06:12 PM, Paul Sandoz wrote:
> 
>>  We may also want to look at related enhancements like unmapping
>> buffers. I think those pieces are sufficient decoupled that they
>> won't be dependencies for the pmem API though, unlike other factors
>> such as the availability of test hardware.
>>
> That’s tricky! We have been through many discussions over the years
> on how to achieve this without much resolution. Andrew Haley came up
> with an interesting solution which IIRC requires the
> deallocating/unmapping thread to effectively reach safe point and
> wait for all other threads to pass through a check point. Project
> Panama is looking at the explicit scoping of resources, perhaps also
> resources that are thread confined or owned. My sense is Project
> Panama will eventually push strongly on this area and that’s where
> we should focus our efforts.

Yeah, perhaps so.  I've been waiting to come up for air to have enough
time to handle the ByteBuffer.unmap() bug.  I can see the advantage of
handling it at a static language level, but the solutions aren't
necessarily exclusive.

-- 
Andrew Haley
Java Platform Lead Engineer
Red Hat UK Ltd. <https://www.redhat.com>
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