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Date: Thu, 7 Apr 2005 02:30:00 +0200 (CEST)
From: Roman Zippel <zippel@linux-m68k.org>
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To: Dave Hansen <haveblue@us.ibm.com>
cc: Andrew Morton <akpm@osdl.org>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       linux-mm <linux-mm@kvack.org>, Andy Whitcroft <apw@shadowen.org>
Subject: Re: [PATCH 1/4] create mm/Kconfig for arch-independent memory options
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Hi,

On Wed, 6 Apr 2005, Dave Hansen wrote:

> > Why is this choice needed at all? Why would one choose SPARSEMEM over 
> > DISCONTIGMEM?
> 
> For now, it's only so people can test either one, and we don't have to
> try to toss DICONTIGMEM out of the kernel in fell swoop.  When the
> memory hotplug options are enabled, the DISCONTIG option goes away, and
> SPARSEMEM is selected as the only option.
> 
> I hope to, in the future, make the options more like this:
> 
> config MEMORY_HOTPLUG...
> config NUMA...
> 
> config DISCONTIGMEM
> 	depends on NUMA && !MEMORY_HOTPLUG
> 
> config SPARSEMEM
> 	depends on MEMORY_HOTPLUG || OTHER_ARCH_THING
> 
> config FLATMEM
> 	depends on !DISCONTIGMEM && !SPARSEMEM

I was hoping for this too, in the meantime can't you simply make it a 
suboption of DISCONTIGMEM? So an extra option is only visible when it's 
enabled and most people can ignore it completely by just disabling a 
single option.

> > Help texts such as "If unsure, choose <something else>" make 
> > the complete config option pretty useless.
> 
> They don't make it useless, they just guide a clueless user to the right
> place, without them having to think about it at all.  Those of us that
> need to test the various configurations are quite sure of what we're
> doing, and can ignore the messages. :)
> 
> I'm not opposed to creating some better help text for those things, I'm
> just not sure that we really need it, or that it will help end users get
> to the right place.  I guess more explanation never hurt anyone.

Some basic explanation with a link for more information can't hurt.

bye, Roman
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