RFR(M): 8204908: Allocation of Old generation of Java Heap on alternate memory devices.

[Kirk Pepperdine]

> On Jun 18, 2018, at 8:18 AM, David Holmes <david.holmes at oracle.com> wrote:
> 
> On 13/06/2018 4:11 PM, Thomas Stüfe wrote:
>> Hi,
>> (adding hs-runtime)
> 
> Thanks for that Thomas.
> 
> I also had a cursory glance. This is not really a Request for Review (RFR) as suggested by the email subject but more a "request for comment". The JEP is still a draft and this is a long way from being in a form that could be integrated. As a POC/prototype this may be functional but it is far too intrusive to me to be considered as the final form for this kind of change. The level of abstraction seems wrong; the use of nvdimm is everywhere. Ideally I would have expected the use of an alternate memory device to be hidden behind the address range - ie you just point the old gen to the alternate memory device, mapping into a given address range for the process and it "just works”.

+1,  this feels like it should be managed by device drivers mapped to an address range. That said, I’m not sure that the JVM could take advantage of this is a completely transparent way.

Kind regards,
Kirk