Subject: Re: [PATCH] Increase the upper bound on NR_CPUS.

From: Michael Ellerman <[email-masked]>
Date: Thu, 29 Nov 2007 15:44:13 +1100

On Thu, 2007-11-29 at 15:23 +1100, Tony Breeds wrote:
> On Thu, Nov 29, 2007 at 03:17:16PM +1100, Michael Ellerman wrote:
> > On Thu, 2007-11-29 at 15:16 +1100, Tony Breeds wrote:
> > > Signed-off-by: Tony Breeds <[email-masked]>
> > > 
> > > ---
> > > why not?
> > 
> > How big is say a pseries_defconfig with NR_CPUS = 1024 ?
> 
> This is a ppc64_defconfig, with a couple of extra patches, and
> NR_CPUS=1024
> 
> tony@Sprygo:~/scratch/working$ size ../working_out/arch/powerpc/boot/zImage.{pmac,pseries,iseries} ../working_out/vmlinux
>    text    data     bss      dec     hex filename
> 3697092    5356   48232  3750680  393b18 ../working_out/arch/powerpc/boot/zImage.pmac
> 3697092    5356   48232  3750680  393b18 ../working_out/arch/powerpc/boot/zImage.pseries
> 8101340 4994176  815544 13911060  d44414 ../working_out/arch/powerpc/boot/zImage.iseries
> 8101340 4994176  815544 13911060  d44414 ../working_out/vmlinux

OK, not too bad for the zImage, but the vmlinux has grown a bit, we
obviously have lots of foo[NR_CPUS].

NR_CPUS = 32 vs 1024

   text    data     bss     dec     hex filename
7889287 1786256  529248 10204791         9bb677 vmlinux
7901531 4946864  814432 13662827         d07a6b vmlinux

cheers

-- 
Michael Ellerman
OzLabs, IBM Australia Development Lab

wwweb: http://michael.ellerman.id.au
phone: +61 2 6212 1183 (tie line 70 21183)

We do not inherit the earth from our ancestors,
we borrow it from our children. - S.M.A.R.T Person