Subject: Re: sysctl HW_PAGESIZE
To: Emmanuel Dreyfus <manu@netbsd.org>
From: Alfred Perlstein <bright@mu.org>
List: tech-perform
Date: 02/23/2002 12:48:13
* Emmanuel Dreyfus <manu@netbsd.org> [020223 12:38] wrote:
> > Afaik several arches allow for variable page sizes, not just 4k vs 4meg
> > pages either, something like 4, 8 and 16k pages I've _heard_ for ia64,
> > it's possible that a system administrator (if the OS allowed it) would
> > want larger pages on large memory machines or smaller pages on small
> > memory machines, therefore doing at compile time isn't a really good
> > idea.  It might make sense to somehow hand that info over to the process
> > during exec() somehow, a lame way would be to use the environment space
> > but I'm sure there's more clever ways of doing something like that.
> 
> Ok, it was just a stupid question. :o)
> It seems we are moving toward an uniform dynamic ELF system, then it
> makes sense to get the value from the ELF auxiliary table and fallback
> to the system call if it does not work. 

I'm not familiar with 'uniform dynamic ELF' but if it means the kernel
or interpreter loads various paramters someplace into the process's
address space then it makes sense to me. :)

> 
> Using an environemement variable means you will have an environement
> variable name that could conflict with a user variable name, dosn't it?

That's why that method was qualified with "lame". :)

-- 
-Alfred Perlstein [alfred@freebsd.org]
'Instead of asking why a piece of software is using "1970s technology,"
 start asking why software is ignoring 30 years of accumulated wisdom.'
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