Fwd: RAM usage

[amcmorl at gmail.com (Angus McMorland)]

Woops - sent this off-list by accident - it's rather late/early here
and I should be asleep. Sorry, Tzafrir for the double sending.

---------- Forwarded message ----------
From: Angus McMorland <amcmorl at gmail.com>
Date: 16 Sep 2007 01:30
Subject: Re: RAM usage
To: Tzafrir Cohen <tzafrir.cohen at xorcom.com>


On 15/09/2007, Tzafrir Cohen <tzafrir.cohen at xorcom.com> wrote:
> On Sat, Sep 15, 2007 at 07:55:02AM -0300, Ben Armstrong wrote:
> > On Sat, 15 Sep 2007 11:18:09 +1200
> > "Angus McMorland" <amcmorl at gmail.com> wrote:
> > >              total       used       free     shared    buffers     cached
> > > Mem:        906588     287164     619424          0      41908     173652
> > > -/+ buffers/cache:      71604     834984
> > > Swap:            0          0          0
> >
> > Perhaps you have custom compiled a kernel and have not set CONFIG_HIGHMEM=y?
>
> On the default Etch kernel it isn't.
>
> $ grep CONFIG_HIGHMEM /usr/src/linux-headers-2.6.18-4-486/.config
> CONFIG_HIGHMEM4G is not set
> CONFIG_HIGHMEM64G is not set

Indeed - I now suspect this is the problem - the config file in my
live chroot also shows:

CONFIG_NOHIGHMEM=y
# CONFIG_HIGHMEM4G is not set
# CONFIG_HIGHMEM64G is not set

On my laptop (i.e. not from a live CD), running linux-image-2.6-686,
these settings look different:

# CONFIG_NOHIGHMEM is not set
CONFIG_HIGHMEM4G=y
# CONFIG_HIGHMEM64G is not set
CONFIG_PAGE_OFFSET=0xC0000000
CONFIG_HIGHMEM=y

So, I'm currently trying to build a 686-based live CD to check if that
is the difference. Interestingly starting with "lh_config -a i686"...
doesn't force the install of the 686 image, and rather the 486
packages:

The following NEW packages will be automatically installed:
  busybox file initramfs-tools klibc-utils libklibc libmagic1 libvolume-id0
  linux-image-2.6.21-2-486 squashfs-modules-2.6.21-2-486 sudo udev
  unionfs-modules-2.6.21-2-486 user-setup

are still used. Is this expected? How can I specify the 686 packages
instead of the 486 ones. I know all the machines I want to run on are
Core 2 Duos, so limiting the architecture should be fine for my needs.
Otherwise, I suppose I can try adding the 686-specific packages into
my packages list. Will this just work or will I need to de-activate
the 486 packages too somehow?

Thanks all for your help - certainly seems like we're making progress,

A.
-- 
AJC McMorland, PhD Student
Physiology, University of Auckland