Re: uarea swap-out

Mindaugas Rasiukevicius wrote:
> matthew green <[email protected]> wrote:
>> i'm really curious how this affects platforms with very
>> few hardware pages, like acorn26.
>>
> 
> I cannot measure that empirically, therefore CC'ing port-acorn26 and
> port-acorn32 lists. There are few points regarding this:
> 
> - Merge of lwp_cache and uarea (it puts struct lwp, pcb and kstack together)
>   should have positive effect i.e. it would increase the utilisation of pages.
> 
> - The criteria when LWP can be swapped-out is relatively strict i.e. there
>   are already many states when it cannot, see swappable() in uvm_glue.c.
> 
> - If your machine starts swapping uareas, I think it is already quite a
>   hammer, especially for machines like acorn26/32.
> 
> Newer patch removing uarea swap-out:
> 
I'll give it a try on an acorn32 machine next weekend. I assume the 
patch is for a current kernel.

Mike