4GB memory

[Giles Orr]

On Wed, Apr 2, 2008 at 10:42 AM, D. Hugh Redelmeier <hugh-pmF8o41NoarQT0dZR+AlfA at public.gmane.org> wrote:
>  In the XP days, the swap file was unmoveable.  You could turn off
>  static swap file allocation and then defrag & shrink, then turn it on
>  again.  I don't know if this applies in the MS Vista era.

I'll try that.  Thanks.

>  I had to buy MS Vista recovery disks.  I could not boot Vista for
>  the first time (after owning the machine for ~5 months).  Acer's one
>  year warranty did not apply to Vista -- that was only 90 days (grrr).
>  It turns out that under some conditions Vista won't boot if you fiddle
>  with the MBR, which, of course, installing Linux does.  I haven't got
>  the measure of this problem.  Perhaps it is only the first boot that
>  won't work.

It occurs to me that I haven't booted Vista since I let Debian/GRUB
mess with the MBR ...  I should probably do that.  But Dell does seem
to have provided Recovery disks.

>  | I bought the machine with 4GB of memory (4 sticks of 1GB).  I wasn't
>  | surprised to see Vista displaying 3.2GB, although it amuses me to no
>  | end that you need 2GB to run it decently and you can't use more than
>  | 3GB ... that's a pretty small window of opportunity.
>
>  According to Wikipedia's article on PAE
>   http://en.wikipedia.org/wiki/Physical_Address_Extension
>  MS Vista SP1 can use PAE to get at all the memory.  So install SP1.

SP1 has received such extraordinarily bad reviews that I think I'll
wait: I'm not using Vista much (I haven't booted it since I installed
Debian three or four days ago) so I'll let others work out the kinks
on that one.

>  |  But I was
>  | surprised to find that Debian testing displays very much the same
>  | thing with "free", 3287MB even after I installed and booted kernel
>  | 2.6.24-1-686-bigmem.
>
>  That is surprising.  If you use dmesg you should see early on what the
>  kernel thinks the physical memory blocks are.  Here's from my machine:
>  BIOS-provided physical RAM map:
>   BIOS-e820: 0000000000000000 - 000000000009fc00 (usable)
>   BIOS-e820: 000000000009fc00 - 00000000000a0000 (reserved)
>   BIOS-e820: 00000000000e7000 - 0000000000100000 (reserved)
>   BIOS-e820: 0000000000100000 - 000000003ffc0000 (usable)
>   BIOS-e820: 000000003ffc0000 - 000000003ffd0000 (ACPI data)
>   BIOS-e820: 000000003ffd0000 - 0000000040000000 (ACPI NVS)
>   BIOS-e820: 00000000fec00000 - 00000000fec01000 (reserved)
>   BIOS-e820: 00000000fee00000 - 00000000fee01000 (reserved)
>   BIOS-e820: 00000000ff7c0000 - 0000000100000000 (reserved)

That's ... nice, unfortunately I can't read it at all.  You'll see
below that my listing is very similar.  Anyone who can read it feel
free to comment ...

>  I use x86-64 on my machines that can handle it.  This hardly ever
>  causes problems these days, at least in the Red Hat / Fedora / CentOS
>  world.  I admit that the advantages on a desktop are minor; sane
>  large-memory handling is one of them.

This may fall into the dumb question category ... but I should ask:
the c2d and c2q processors are 64 bit, right?  Aside from known issues
like 32 bit Flash, is there any reason I shouldn't install 64 bit
Debian?

Here's a part of "dmesg" output:

BIOS-provided physical RAM map:

 BIOS-e820: 0000000000000000 - 000000000009e800 (usable)

 BIOS-e820: 000000000009e800 - 00000000000a0000 (reserved)

 BIOS-e820: 00000000000f0000 - 0000000000100000 (reserved)

 BIOS-e820: 0000000000100000 - 00000000cf590000 (usable)

 BIOS-e820: 00000000cf590000 - 00000000cf5e3000 (ACPI NVS)

 BIOS-e820: 00000000cf5e3000 - 00000000cf5f0000 (ACPI data)

 BIOS-e820: 00000000cf5f0000 - 00000000cf600000 (reserved)

 BIOS-e820: 00000000e0000000 - 00000000f0000000 (reserved)

 BIOS-e820: 00000000fec00000 - 0000000100000000 (reserved)

2421MB HIGHMEM available.

896MB LOWMEM available.

found SMP MP-table at 000f3f00

NX (Execute Disable) protection: active

Entering add_active_range(0, 0, 849296) 0 entries of 256 used

Zone PFN ranges:

  DMA             0 ->     4096

  Normal       4096 ->   229376

  HighMem    229376 ->   849296

Movable zone start PFN for each node

early_node_map[1] active PFN ranges

    0:        0 ->   849296

On node 0 totalpages: 849296

  DMA zone: 32 pages used for memmap

  DMA zone: 0 pages reserved

  DMA zone: 4064 pages, LIFO batch:0

  Normal zone: 1760 pages used for memmap

  Normal zone: 223520 pages, LIFO batch:31

  HighMem zone: 4843 pages used for memmap

  HighMem zone: 615077 pages, LIFO batch:31

  Movable zone: 0 pages used for memmap

DMI 2.5 present.


-- 
Giles
http://www.gilesorr.com/
gilesorr-Re5JQEeQqe8AvxtiuMwx3w at public.gmane.org
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