Re: [RFC PATCH 2/2] mm/vmscan.c: Prevent allocating shrinker_info on offlined nodes

[David Hildenbrand]

>> But there might be more missing. Onlining a new zone will get more
>> expensive in setups with a lot of possible nodes (x86-64 shouldn't
>> really be an issue in that regard).
> 
> Honestly, I am not really concerned by platforms with too many nodes
> without any memory. If they want to shoot their feet then that's their
> choice. We can optimize for those if they ever prove to be standar.
>  
>> If we want stable backports, we'll want something simple upfront.
> 
> For stable backports I would be fine by doing your NODE_DATA check in
> the allocator. In upstream I think we should be aiming for a more robust
> solution that is also easier to maintain further down the line. Even if
> that is an investment at this momemnt because the initialization code is
> a mess.
> 

Agreed. I would be curious *why* we decided to dynamically allocate the
pgdat. is this just a historical coincidence or was there real reason to
not allocate it for all possible nodes during boot?

-- 
Thanks,

David / dhildenb