Re: [RFC] 2.3.39 zone balancing

[Kanoj Sarcar]

> 
> In this patch against 2.3.42 I fixed a cupole of bugs in the new memory
> balancing code that is been merged in the latest 2.3.x kernels:
> 
> 	ftp://ftp.*.kernel.org/pub/linux/kernel/people/andrea/patches/v2.3/2.3.42/MM-balance-1.gz
> 
> Comments are welcome.
> 
> Andrea
> 

I like the part of being able to poke kswapd via an interface
(wake_up_interruptible), this is something that might help numa
allocators ....

I hate the part of adding in more magic numbers to the balancing
logic, unless you can demonstrate how it helps. I know, 2.2
uses these magic numbers to set freepages.*, but I can't see a
logic to having min/max for zones. It is still probably acceptable 
to have the magic numbers in 2.3 for freepages.* setting (at 
least until we have a zone aware kswapd), for global stuff. If
you do decide to put in the min/max stuff, make sure to add
in the smarts to specify it from the command line (in 
setup_mem_frac).

The ZONE_BALANCED macro is currently a good way to see whether 
we really want to do more compute intensive classfree(). 

Kanoj