Re: [PATCH] mm: add config option to select the initial overcommit mode

From: Sebastian Frias
Date: Fri May 13 2016 - 11:37:30 EST


Hi Alan,

On 05/13/2016 05:04 PM, One Thousand Gnomes wrote:
>>> Perhaps Sebastian's choice could be made to depend on CONFIG_EMBEDDED,
>>> rather than CONFIG_EXPERT?
>>
>> Even if the overcommit behavior is different on those systems the
>> primary question hasn't been answered yet. Why cannot this be done from
>> the userspace? In other words what wouldn't work properly?
>
> Most allocations in C have no mechanism to report failure.
>
> Stakc expansion failure is not reportable. Copy on write failure is not
> reportable and so on.

But wouldn't those affect a given process at at time?
Does that means that the OOM-killer is woken up to kill process X when those situations arise on process Y?

Also, under what conditions would copy-on-write fail?

Best regards,

Sebastian