Help porting Linux app - getting Free Memory and Real Memory

[Rod Person]

On 03/29/13 08:34, Lowell Gilbert wrote:
> Peter Jeremy <peter at rulingia.com> writes:
>
>> On 2013-Mar-29 20:27:27 -0400, Rod Person <rodperson at rodperson.com> wrote:
>>> Everything is going we except that the program gives warnings that there
>>> isn't enough free memory on the system to perform certain actions.
>> That premise sounds suspiciously like the upstream author doesn't
>> understand how Unix VM works.
> To be more blunt, these checks may well be useless on Linux.
> On a quick look, you seem to maintain three ports: idutils, mspdebug,
> and jogl. I wouldn't expect a free-memory check to be appropriate on any
> of those.
Really?  The port in question if graphics/fotoxx. I have no involvement
in the others. For the latter two, I'm not even sure what they are.

> In any case, the definition of "free memory" is different between the VM
> systems in Linux and BSD . Even if the checks do make sense, the FreeBSD
> implementation would at the minimum have to include all of the pages
> that are allocated but not mapped.
Yes I have read this. Fotoxx uses free memory calculation when applying
effects to images.  It looks at the image size then calculates how much
memory it needs to apply an effect, such as image sharpening. For
example, on a 4.5MB jpg file it seems to calculate that 40MB of free
memory is need to apply sharpening to the image.  40MB doesn't seem like
a lot of memory to me, but since the application way of figuring free
memory is Linux specific the warning dialog appear, although it seem to
have no ill effect on actually applying the sharpening effect.

Rod