loading more than 2GB of matrixes?

Sep 3, 2007 at 5:19pm

loading more than 2GB of matrixes?

Hi,

I am trying to load a bunch of video clips into jit.qt.movie objects,
more than 2GB worth. When I simply create enough jit.qt.movie
objects (about 200 of them, at 320×240, inside a poly~) and cross
this threshold of 2GB, max immediately crashes, or pauses for awhile
unresponsively and then crashes. The same happens when I try to
allocate jit.matrix objects of a total size that is greater than 2GB
- say, a single [jit.matrix 4 char 320 240 2000] or 7 of [jit.matrix
160 120 1000]. (Each [jit.matrix 320 240 1] is about 300K)

My question is, how come there is this limit when creating matrices
but not when loading a gigantic jit.qt.movie-read file into ram?
That way, I can load 5GB of movie data (into 16GB or RAM, for some
reason…). If OS X is 64-bit, ow come Max is limited to 32 bits of
address space? I’m probably missing something here.

Best
Evan

#33517
Sep 3, 2007 at 5:49pm

On Sep 3, 2007, at 10:19 AM, evan.raskob [lists] wrote:

> My question is, how come there is this limit when creating matrices
> but not when loading a gigantic jit.qt.movie-read file into ram?
> That way, I can load 5GB of movie data (into 16GB or RAM, for some
> reason…). If OS X is 64-bit, ow come Max is limited to 32 bits
> of address space? I’m probably missing something here.

Like many applications, Max is currently only a 32 bit application.
You will need to figure out a strategy for using the disk to your
advantage.

If you are trying a *loadram* message to jit.qt.movie it will also
not load the RAM, if not crash. When you just open a file via read,
it is not loaded into RAM. Perhaps this is the discrepancy you are
seeing.

-Joshua

#111735
Sep 4, 2007 at 8:19pm

Hi Joshua,

On Sep 3, 2007, at 6:49 PM, Joshua Kit Clayton wrote:

>
> On Sep 3, 2007, at 10:19 AM, evan.raskob [lists] wrote:
>
>> My question is, how come there is this limit when creating
>> matrices but not when loading a gigantic jit.qt.movie-read file
>> into ram? That way, I can load 5GB of movie data (into 16GB or
>> RAM, for some reason…). If OS X is 64-bit, ow come Max is
>> limited to 32 bits of address space? I’m probably missing
>> something here.
>
> Like many applications, Max is currently only a 32 bit application.
> You will need to figure out a strategy for using the disk to your
> advantage.

I see. Thanks for confirming that.

> If you are trying a *loadram* message to jit.qt.movie it will also
> not load the RAM, if not crash. When you just open a file via read,
> it is not loaded into RAM. Perhaps this is the discrepancy you are
> seeing.

Using Activity monitor, I load a ~5GB Quicktime file and don’t see a
huge increase in RAM. After next sending it a “loadram” message I
see RAM usage jump to ~16GB (on a 16GB RAM, Quad-processor Intel
Mac), and movie plays very well. Unless there is something odd with
Activity Monitor, or that I missing something important, doesn’t this
mean that entire 5GB of the movie is now in RAM?

thanks
Evan

> -Joshua
>

#111736
Sep 4, 2007 at 8:40pm

On Sep 4, 2007, at 1:19 PM, evan.raskob [lists] wrote:

>> If you are trying a *loadram* message to jit.qt.movie it will also
>> not load the RAM, if not crash. When you just open a file via
>> read, it is not loaded into RAM. Perhaps this is the discrepancy
>> you are seeing.
>
> Using Activity monitor, I load a ~5GB Quicktime file and don’t see
> a huge increase in RAM. After next sending it a “loadram” message
> I see RAM usage jump to ~16GB (on a 16GB RAM, Quad-processor Intel
> Mac), and movie plays very well. Unless there is something odd
> with Activity Monitor, or that I missing something important,
> doesn’t this mean that entire 5GB of the movie is now in RAM?

Perhaps QT now has some ability to load into the RAM of another
process, or on the fly RAM disk, or some other trickiness that I was
unaware of. You might also be able to use a RAM disk to your
advantage for read/writing matrices faster than to/from disk.

-Joshua

#111737
Sep 6, 2007 at 8:23am

I had problems with the 2gb limit too. Took me quite some time to figure out what caused the crash. Would it be an idea to generate an alert if the 2gb limit is reached?

Mattijs

#111738

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