Re: When should ralloc.c be used?

[Jérémie Courrèges-Anglas]

Daniel Colascione <address@hidden> writes:

> On 10/24/2016 08:40 AM, Eli Zaretskii wrote:
>>> From: Stefan Monnier <address@hidden>
>>> Cc: address@hidden,  address@hidden
>>> Date: Mon, 24 Oct 2016 10:37:19 -0400
>>>
>>>> Using mmap has disadvantages: when you need to enlarge buffer text,
>>>> and that fails (because there are no more free pages/addresses after
>>>> the already allocated region), we need to copy buffer text to the new
>>>> allocation.
>
> 64-bit address spaces are *huge*. What about just making every buffer
> allocation 2GB long or so, marked PROT_NONE? You don't actually have to
> commit all that memory --- all you've done is set aside that address
> space.

IIUC you suggest relying on memory overcommit.  That doesn't sound
portable at all.  Not all OSes do overcommit and the ones who do
generally provide a way to disable it.

-- 
jca | PGP : 0x1524E7EE / 5135 92C1 AD36 5293 2BDF  DDCC 0DFA 74AE 1524 E7EE