[Python-Dev] PEP 554 v2 (new "interpreters" module)

[Nick Coghlan]

On 10 September 2017 at 03:54, Nathaniel Smith <njs at pobox.com> wrote:
> On Sep 9, 2017 9:07 AM, "Nick Coghlan" <ncoghlan at gmail.com> wrote:
>
>
> To immediately realise some level of efficiency benefits from the
> shared memory space between the main interpreter and subinterpreters,
> I also think these low level FIFOs should be defined as accepting any
> object that supports the PEP 3118 buffer protocol, and emitting
> memoryview() objects on the receiving end, rather than being bytes-in,
> bytes-out.
>
>
> Is your idea that this memoryview would refer directly to the sending
> interpreter's memory (as opposed to a copy into some receiver-owned buffer)?

There are two possibilities that I think can be made to work. Option
one would be a memoryview subclass that:

1. Also stores a reference to the source interpreter
2. Temporarily switches back to that interpreter when acquiring or
releasing a buffer view

The receiving interpreter would then also be able to acquire a
suitable referencing to the sending interpreter for the message in
order to establish bidirectional communications.

Option two would be the same general idea, but with a regular
memoryview placed in front of the subinterpreter aware variant
(although it's less clear how we'd establish bidirectional comms
channels in that case).

Cheers,
Nick.

-- 
Nick Coghlan   |   ncoghlan at gmail.com   |   Brisbane, Australia