Re: MM/VM todo list

[Daniel Phillips]

On Fri, 05 Jan 2001, Rik van Riel wrote:
> Hi,
> 
> here is a TODO list for the memory management area of the
> Linux kernel, with both trivial things that could be done
> for later 2.4 releases and more complex things that really
> have to be 2.5 things.
> 
> Most of these can be found on http://linux24.sourceforge.net/ too
> 
> Trivial stuff:
> * VM: better IO clustering for swap (and filesystem) IO
>   * Marcelo's swapin/out clustering code
>   * ->writepage() IO clustering support
>   * page_launder()/->writepage() working together in avoiding
>     low-yield (small cluster) IO at first, ...
> * VM: include Ben LaHaise's code, which moves readahead to the
>   VMA level, this way we can do streaming swap IO, complete with
>   drop_behind()
> * VM: enforce RSS ulimit
> 
> 
> Probably 2.5 era:
> * VM: physical->virtual reverse mapping, so we can do much
>   better page aging with less CPU usage spikes 
> * VM: move all the global VM variables, lists, etc. into the
>   pgdat struct for better NUMA scalability
> * VM: per-node kswapd for NUMA
> * VM: thrashing control, maybe process suspension with some
>   forced swapping ?             (trivial only in theory)
> * VM: experiment with different active lists / aging pages
>   of different ages at different rates + other page replacement
>   improvements
> * VM: Quality of Service / fairness / ... improvements
> 
> 
> Additions to this list are always welcome, I'll put it online
> on the Linux-MM pages (http://www.linux.eu.org/Linux-MM/) soon.

I'd like to suggest variable sized pages as a research topic.  It's not
clear whether we're talking 2.5 or 2.7 here.

-- 
Daniel