RFC: Safe OOM during evac

[Roman Kennke]

Am 20.10.2017 um 15:35 schrieb Zhengyu Gu:
>>> Is this the direction we are heading? 'cause I would need to revive 
>>> pin_object() patch
>> Currently we're heading nowhere :-) I'm building a prototype to try 
>> to make a safe OOM-during-evac handling. If string dedup does modify 
>> evacuated objects, I'll make this safe OOM-during-evac handling for 
>> GC workers too. That should resolve your problem, right?
>
> Probably not, 'cause it still sees from-space pointers.
Seeing or even writing to from-space oops is not generally bad. It is 
not an absolute requirement that we never write to from-space oops. The 
absolute requirement is that we must not write to from-space oops if 
there is a to-space copy. This is exactly what this patch is going to 
prevent.

Roman