[PLUG-TALK] Laptop Memory Question

Paul Heinlein heinlein at madboa.com
Thu Mar 10 16:13:07 PST 2011

On Thu, 10 Mar 2011, Keith Lofstrom wrote:

> The dmidecode utility is cool to learn about.  But, when I run it on 
> my laptop, it says:
> Physical Memory Array
>        ...
>        Maximum Capacity: 2 GB
>        ...
> I am currently running with 3 GB.  I know the machine won't take 4 
> GB.  The reported number is the "official" number for a Thinkpad 
> T60, which is often lower than what actually works.

I suppose it's like overclocking -- some amount of pushing the 
official limits will increase system performance, but there comes a 
point where the system can't handle it. :-)

> On the other hand, aren't there are memory limits for 32 bit linux? 
> Or at least some magic needed for grub.conf?  Any issues with 
> suspend, when the RAM gets large?

There are hard per-process memory limits for 32-bit Linux. It used to 
be that 32-bit systems were subject to a system limit of 4 GB of RAM, 
but CPUs with the 'pae' feature can run PAE kernels (which use mapping 
techniques reminiscent of "high" memory in DOS days) to extend that 
limit to 64 GB.

Paul Heinlein <> heinlein at madboa.com <> http://www.madboa.com/

More information about the PLUG-talk mailing list