RFR(M): 8171181: Supporting heap allocation on alternative memory devices

[Kharbas, Kishor]

Hi Andrew!

Thanks for the clarification. I understand what you mean now.

I agree if NUMA is supported by the filesystem, it will be very useful and should be made available.
To do that, I have to find if the filesystem supports APIs to serve the same purpose as OS numa calls.

Thanks
-Kishor

> -----Original Message-----
> From: Andrew Haley [mailto:aph at redhat.com]
> Sent: Tuesday, March 7, 2017 12:36 AM
> To: Kharbas, Kishor <kishor.kharbas at intel.com>; hotspot-runtime-
> dev at openjdk.java.net
> Subject: Re: RFR(M): 8171181: Supporting heap allocation on alternative
> memory devices
> 
> On 06/03/17 21:19, Kharbas, Kishor wrote:
> > I don't think there will be failures if that happens. The user needs to be let
> known that NUMA is not supported if he tries to use NUMA in conjunction to
> this flag.
> 
> I'm wondering if perhaps I'm not speaking clearly.  Please, let me spell out my
> thinking:
> 
> a.  This flag can be used by the DAX filesystem, but can be used by any
> filesystem.
> 
> b.  For example, it might be used to put the heap onto a file in, say, a RAM-
> backed file where NUMA is supported.
> 
> c.  On such a system, NUMA might be available and useful.
> 
> d.  Therefore it is not appropriate to tell people that NUMA is not supported
> when you do not know that it is not supported.
> 
> Perhaps I have made some mistake in my reasoning here.
> 
> Andrew.