Warp wrote:

> Tom Austin <taustin> wrote:
>> It looks like you know what you are doing, but here are some things I
>> have run across regarding memory - based on 32 bit systems.
> 
>> A single application (thread) is limited to using 2GB or 3GB depending
>> on your OS and settings within the OS.
> 
>   Don't base your answer on 32-bit systems since he is using a 64-bit one.
> 
>   A friend of mine has an amd64 and he tried how much memory he can
> allocate in linux. In linux you can actually allocate more memory than
> is physically available (even when counting swap space). It's only when
> you try to *use* more memory than what is physically available when it is
> not possible.
>   I don't remember exactly how much he could allocate, but it was less
> than 2^64. However, it was way over 2^32. It might have been something
> like 2^48 or whatever. I don't know why there's such a limit, but I assume
> that his motherboard limits the address space of the system to that
> (it's not unusual for motherboards of new processors to not to support
> everything the processor could).
> 
>   I don't know why he cannot use more than 3GB in his system, though.
> 
I couldn't use the memory because something went wrong when I switched
kernels. I upgraded my machine from 2Gb to 4 Gb and had to switch to the
"big" kernel. It supports >3Gb memory. In my case the "bigsmp" kernel since
I have an AMD X2 (dual core).
I have since reinstalled my system and for the sake of testing ran renders
that needed > 10Gb of memory and that went just fine.

-- 
Ger

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