Ubuntu Does Not See All My Memory

Thanks for your bug report. Could you please post the output of the 'free' command? Thanks in advance.

Here you go:

jeremy@jeremy-desktop:~$ free
             total used free shared buffers cached
Mem: 1027092 701608 325484 0 27584 410796
-/+ buffers/cache: 263228 763864
Swap: 3004112 0 3004112

On Sunday February 25 2007 11:21:13 pm Brian Murray wrote:
> Thanks for your bug report. Could you please post the output of the
> 'free' command? Thanks in advance.
>
> ** Changed in: Ubuntu
> Assignee: (unassigned) => Brian Murray
> Status: Unconfirmed => Needs Info

What could be going on is that the system has integrated graphics, which borrows some memory from RAM since there isn't any dedicated graphics memory. That's a possibility for why the number appears smaller than it should be.

Not in my case. Integrated graphics and shared memory are both disabled in
the bios, and I use an Nvidia PCI-Express card. I have a Windows dual boot,
and Windows sees all 1014MB of my RAM.

On 2/26/07, Andrew Ash <email address hidden> wrote:
>
> What could be going on is that the system has integrated graphics, which
> borrows some memory from RAM since there isn't any dedicated graphics
> memory. That's a possibility for why the number appears smaller than it
> should be.
>
> --
> Ubuntu Does Not See All My Memory
> https://launchpad.net/bugs/87957
>

Try running 'dmesg | grep -in Memory' in a console; one of the lines will read something like "Memory: 1029372k/1048512k available (...)". In this example, 1048512k would be the total amount detected and usable by the kernel.

Some of it is reserved and therefore doesn't show up as available/installed memory to the rest of the system (including applications such as 'free' or system monitors).

I'll try that when I get home. Just want to make sure you guys understand
me though, Windows sees all 1014MB of RAM, so there is no reason for Ubuntu
not to.

On 2/26/07, yamal <email address hidden> wrote:
>
> Try running 'dmesg | grep -in Memory' in a console; one of the lines
> will read something like "Memory: 1029372k/1048512k available (...)". In
> this example, 1048512k would be the total amount detected and usable by
> the kernel.
>
> Some of it is reserved and therefore doesn't show up as
> available/installed memory to the rest of the system (including
> applications such as 'free' or system monitors).
>
> --
> Ubuntu Does Not See All My Memory
> https://launchpad.net/bugs/87957
>

Here is the output of the command that was requested:

jeremy@jeremy-desktop:~$ dmesg | grep -in Memory
77:[ 35.165972] Memory: 1020352k/1047488k available (2196k kernel code,
26748k reserved, 1138k data, 300k init)
161:[ 36.276201] Freeing initrd memory: 6437k freed
211:[ 36.334700] Freeing unused kernel memory: 300k freed

On Monday February 26 2007 12:48:04 pm yamal wrote:
> Try running 'dmesg | grep -in Memory' in a console; one of the lines
> will read something like "Memory: 1029372k/1048512k available (...)". In
> this example, 1048512k would be the total amount detected and usable by
> the kernel.
>
> Some of it is reserved and therefore doesn't show up as
> available/installed memory to the rest of the system (including
> applications such as 'free' or system monitors).

Some amount of your RAM will be reserved by the hardware to store things like ACPI state - these will show up in the dmesg e820 info as "reserved" or "ACPI NVS" or the like. This is perfectly normal, and a function of your BIOS setup.

That's not the case. If it was, then how would Windows and my Bios both see
memory that Ubuntu doesn't?!

On Tuesday February 27 2007 7:01:18 pm Matthew Garrett wrote:
> Some amount of your RAM will be reserved by the hardware to store things
> like ACPI state - these will show up in the dmesg e820 info as
> "reserved" or "ACPI NVS" or the like. This is perfectly normal, and a
> function of your BIOS setup.
>
> ** Changed in: linux-source-2.6.20 (Ubuntu)
> Status: Unconfirmed => Rejected

By reporting the amount of physical memory in the computer, whereas
Linux reports the amount of memory usable by the OS.

Thank you. But what I still don't understand is that more memory IS usable by
my PC. Upon further inspection, I did determine that Windows only sees 1023MB
RAM, which isn't exactly 1GB but its more than what Kinfocenter shows. I did
determine from the ubuntu forums that 1MB of Ram seems to be reserved
afterall but my concern is that is not what Ubuntu shows. I know that the
leftover RAM will make little to no difference performance-wise, it just
seems like a bug to me.

On Tuesday February 27 2007 7:47:10 pm Matthew Garrett wrote:
> By reporting the amount of physical memory in the computer, whereas
> Linux reports the amount of memory usable by the OS.

As you can see from the dmesg output, the kernel sees 1047488k of memory, that is ~1023 MB (just like any other operating system sees on your system).

Now on Linux, some of these 1023 MB are reserved and used by the kernel. So the total memory available and visible (!) to applications becomes 1023 MB minus whatever the kernel reserves; apparently that makes 1003 MB in your case. Windows showing other numbers is merely a difference in accounting, as Matthew Garrett already pointed out.

Thanks! I understand now. I appreciate everything and your patience.

On 2/28/07, yamal <email address hidden> wrote:
>
> As you can see from the dmesg output, the kernel sees 1047488k of
> memory, that is ~1023 MB (just like any other operating system sees on
> your system).
>
> Now on Linux, some of these 1023 MB are reserved and used by the kernel.
> So the total memory available and visible (!) to applications becomes
> 1023 MB minus whatever the kernel reserves; apparently that makes 1003
> MB in your case. Windows showing other numbers is merely a difference in
> accounting, as Matthew Garrett already pointed out.
>
> --
> Ubuntu Does Not See All My Memory
> https://launchpad.net/bugs/87957
>