Re: Increasing GNAT's heap

[Oliver Kleinke <oliver.kleinke@c-01a.de>]

Am Wed, 13 Nov 2013 18:36:38 +0100
schrieb "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>:

> On Wed, 13 Nov 2013 16:32:13 +0100, Oliver Kleinke wrote:
> 
> > Various chunks of the 32-bit address space are used to address
> > various hardware devices in your machine, e.g. PCI devices, APIC
> > etc. IIRC, how much address space is "wasted" depends on the
> > hardware. So in essence you will never get 4GiB of RAM on a 32-bit
> > machine.
> 
> The question is whether that is closer to 4 or to 2. Under Windows it
> is strictly 2. If Linux reserves lesser chunks of the address space
> then it should be able to compile the program which at its peak takes
> 2.6GB for gnat1 under Windows. However, lesser chunks would mean more
> of them and thus more overhead for handling the process address space.

Should be in the range of 3 - 3.5 GiB, though it depends on your
hardware (try free or cat /proc/meminfo).