Maximum Size of Byte Array

  • Thread starter Thread starter Gerrit
  • Start date Start date
G

Gerrit

Hi all,

I'm getting an OutOfMemoryException when I initialize a byte array in
C# like this:


Byte[] test = new Byte[420000000];


I'm using ASP.NET 2.0. In ASP.Net 1.1 it works fine. So what am I doing

wrong?

What is the maximum length of a byte array?

Can somebody help me? Thanks in advance!

--
Gerrit Horeis

Software Developer
CI-Gate Development & Consulting GmbH
http://www.ci-gate.de
http://www.xira.de
http://www.bitbauer.de
 
ASP.Net 2.0 could be protecting the memory of the server better. That's a
400 MB byte array, which for a lot of servers could be 20% of the available
memory if not more. That could be fine for one and only one user and page
instance, but what happens if even two users work the code that requires a
400 MB byte array allocated. I'm not exactly sure if that's a feasible array
size for a server environment which could be why it's not letting you do it.

Hope this helps,
Mark Fitzpatrick
Microsoft MVP - FrontPage
 
Thank you for your advice!

But I need to use this big array. In my application I want to generate
thumbs and previews from uploaded images and I do not expect that these
images are greater than 100MB in normal case. But in some cases these
images can be about 1 GB. (Perhaps every 6 Month...)

My PC has 2,5 GB of RAM and it's although not able to generate this
array. What do I have to do to make this possible. Is there any system
property in the machine.conig or something else I could do?

Thanks in advance

--
Gerrit Horeis

Software Developer
CI-Gate Development & Consulting GmbH
http://www.ci-gate.de
http://www.xira.de
http://www.bitbauer.de


Mark said:
ASP.Net 2.0 could be protecting the memory of the server better. That's a
400 MB byte array, which for a lot of servers could be 20% of the available
memory if not more. That could be fine for one and only one user and page
instance, but what happens if even two users work the code that requires a
400 MB byte array allocated. I'm not exactly sure if that's a feasible array
size for a server environment which could be why it's not letting you do it.

Hope this helps,
Mark Fitzpatrick
Microsoft MVP - FrontPage

Gerrit said:
Hi all,

I'm getting an OutOfMemoryException when I initialize a byte array in
C# like this:


Byte[] test = new Byte[420000000];


I'm using ASP.NET 2.0. In ASP.Net 1.1 it works fine. So what am I doing

wrong?

What is the maximum length of a byte array?

Can somebody help me? Thanks in advance!

--
Gerrit Horeis

Software Developer
CI-Gate Development & Consulting GmbH
http://www.ci-gate.de
http://www.xira.de
http://www.bitbauer.de
Click to expand...
Click to expand...
 
Gerrit:
I got a good laugh out of this one :)

You can change ASP.NET to use more memory in the processModel...it's set to
60% by default...you can up it..but you'll run into a win32 2gig process
limit (60% of 2.5 is 1.5..so you might be able to get 1.8..but I wouldn't
push it more than that).

Seriously though, some suggestions:

1 - Atleast consider a generic List<Byte> which can have it's size
allocated dynamically..so if you only need 100 mb's, you don't need to
allocate any more.
2 - Is it at all possible to process these images in smaller chunks? or do
you need to do everything all at once?

Also, I THINK depending on where this is defined, the allocation might
happen on the stack instead of the heap...which is much smaller. I'm just
guessing here. I'm I'm right, you'd certainly run up against a limit at 420
megs. The solution might be to define test as an object field...which will
then make it get allocated on the heap..

Karl

--
http://www.openmymind.net/
http://www.fuelindustries.com/


Gerrit said:
Thank you for your advice!

But I need to use this big array. In my application I want to generate
thumbs and previews from uploaded images and I do not expect that these
images are greater than 100MB in normal case. But in some cases these
images can be about 1 GB. (Perhaps every 6 Month...)

My PC has 2,5 GB of RAM and it's although not able to generate this
array. What do I have to do to make this possible. Is there any system
property in the machine.conig or something else I could do?

Thanks in advance

--
Gerrit Horeis

Software Developer
CI-Gate Development & Consulting GmbH
http://www.ci-gate.de
http://www.xira.de
http://www.bitbauer.de


Mark said:
ASP.Net 2.0 could be protecting the memory of the server better. That's a
400 MB byte array, which for a lot of servers could be 20% of the
available
memory if not more. That could be fine for one and only one user and page
instance, but what happens if even two users work the code that requires
a
400 MB byte array allocated. I'm not exactly sure if that's a feasible
array
size for a server environment which could be why it's not letting you do
it.

Hope this helps,
Mark Fitzpatrick
Microsoft MVP - FrontPage

Gerrit said:
Hi all,

I'm getting an OutOfMemoryException when I initialize a byte array in
C# like this:


Byte[] test = new Byte[420000000];


I'm using ASP.NET 2.0. In ASP.Net 1.1 it works fine. So what am I doing

wrong?

What is the maximum length of a byte array?

Can somebody help me? Thanks in advance!

--
Gerrit Horeis

Software Developer
CI-Gate Development & Consulting GmbH
http://www.ci-gate.de
http://www.xira.de
http://www.bitbauer.de
Click to expand...
Click to expand...
Click to expand...
 
Thank you for your answer!

I had already setup this setting in the processmodel-section to 90% but
there is still the same behavior.

If I allocate a 400 MB byte array I Do need this axact size because the
file has this size. I do not allocate 400 MB in every case of course.

The idea to trade the image in chunks is very good.
But I do not know how to load an image in chunks into memory, which
could be compressed (perhaps a jpeg file).

I probably have to decompress this chunk and convert it into a Bitmap
and then save it to Harddisk as chunk "xy".

Is it even possible to work with a compressed chunk of a jpeg file? How
can I determine wich size (height and width) this chunk has (I would
need this info to put the chunks together again after resizing them)

sorry for so many questions...But perhaps you can help again...

Thanks in advance


--
Gerrit Horeis

Software Developer
CI-Gate Development & Consulting GmbH
http://www.ci-gate.de
http://www.xira.de
http://www.bitbauer.de


Gerrit:
I got a good laugh out of this one :)

You can change ASP.NET to use more memory in the processModel...it's set to
60% by default...you can up it..but you'll run into a win32 2gig process
limit (60% of 2.5 is 1.5..so you might be able to get 1.8..but I wouldn't
push it more than that).

Seriously though, some suggestions:

1 - Atleast consider a generic List<Byte> which can have it's size
allocated dynamically..so if you only need 100 mb's, you don't need to
allocate any more.
2 - Is it at all possible to process these images in smaller chunks? or do
you need to do everything all at once?

Also, I THINK depending on where this is defined, the allocation might
happen on the stack instead of the heap...which is much smaller. I'm just
guessing here. I'm I'm right, you'd certainly run up against a limit at 420
megs. The solution might be to define test as an object field...which will
then make it get allocated on the heap..

Karl

--
http://www.openmymind.net/
http://www.fuelindustries.com/


Gerrit said:
Thank you for your advice!

But I need to use this big array. In my application I want to generate
thumbs and previews from uploaded images and I do not expect that these
images are greater than 100MB in normal case. But in some cases these
images can be about 1 GB. (Perhaps every 6 Month...)

My PC has 2,5 GB of RAM and it's although not able to generate this
array. What do I have to do to make this possible. Is there any system
property in the machine.conig or something else I could do?

Thanks in advance

--
Gerrit Horeis

Software Developer
CI-Gate Development & Consulting GmbH
http://www.ci-gate.de
http://www.xira.de
http://www.bitbauer.de


Mark said:
ASP.Net 2.0 could be protecting the memory of the server better. That's a
400 MB byte array, which for a lot of servers could be 20% of the
available
memory if not more. That could be fine for one and only one user and page
instance, but what happens if even two users work the code that requires
a
400 MB byte array allocated. I'm not exactly sure if that's a feasible
array
size for a server environment which could be why it's not letting you do
it.

Hope this helps,
Mark Fitzpatrick
Microsoft MVP - FrontPage

Hi all,

I'm getting an OutOfMemoryException when I initialize a byte array in
C# like this:


Byte[] test = new Byte[420000000];


I'm using ASP.NET 2.0. In ASP.Net 1.1 it works fine. So what am I doing

wrong?

What is the maximum length of a byte array?

Can somebody help me? Thanks in advance!

--
Gerrit Horeis

Software Developer
CI-Gate Development & Consulting GmbH
http://www.ci-gate.de
http://www.xira.de
http://www.bitbauer.de
Click to expand...
Click to expand...
Click to expand...
 
Gerrit:
Unfortunetly I don't know enough about the jpg image format...

I know bitmaps are just an array of X/Y RGBA pixels..

It'd be nice if GDI+ took care of doing this for you, but from my brief
research, it looks like it's an all or nothing scenario...

The only thing I can recommend is that you try to take a look through:
http://groups.google.ca/groups/search?hl=en&q=GDI++large+images&qt_s=Search

I took a quick look and didn't find anything promising though :(

Karl

--
http://www.openmymind.net/
http://www.fuelindustries.com/


Gerrit said:
Thank you for your answer!

I had already setup this setting in the processmodel-section to 90% but
there is still the same behavior.

If I allocate a 400 MB byte array I Do need this axact size because the
file has this size. I do not allocate 400 MB in every case of course.

The idea to trade the image in chunks is very good.
But I do not know how to load an image in chunks into memory, which
could be compressed (perhaps a jpeg file).

I probably have to decompress this chunk and convert it into a Bitmap
and then save it to Harddisk as chunk "xy".

Is it even possible to work with a compressed chunk of a jpeg file? How
can I determine wich size (height and width) this chunk has (I would
need this info to put the chunks together again after resizing them)

sorry for so many questions...But perhaps you can help again...

Thanks in advance


--
Gerrit Horeis

Software Developer
CI-Gate Development & Consulting GmbH
http://www.ci-gate.de
http://www.xira.de
http://www.bitbauer.de


Gerrit:
I got a good laugh out of this one :)

You can change ASP.NET to use more memory in the processModel...it's set
to
60% by default...you can up it..but you'll run into a win32 2gig process
limit (60% of 2.5 is 1.5..so you might be able to get 1.8..but I wouldn't
push it more than that).

Seriously though, some suggestions:

1 - Atleast consider a generic List<Byte> which can have it's size
allocated dynamically..so if you only need 100 mb's, you don't need to
allocate any more.
2 - Is it at all possible to process these images in smaller chunks? or
do
you need to do everything all at once?

Also, I THINK depending on where this is defined, the allocation might
happen on the stack instead of the heap...which is much smaller. I'm just
guessing here. I'm I'm right, you'd certainly run up against a limit at
420
megs. The solution might be to define test as an object field...which
will
then make it get allocated on the heap..

Karl

--
http://www.openmymind.net/
http://www.fuelindustries.com/


Gerrit said:
Thank you for your advice!

But I need to use this big array. In my application I want to generate
thumbs and previews from uploaded images and I do not expect that these
images are greater than 100MB in normal case. But in some cases these
images can be about 1 GB. (Perhaps every 6 Month...)

My PC has 2,5 GB of RAM and it's although not able to generate this
array. What do I have to do to make this possible. Is there any system
property in the machine.conig or something else I could do?

Thanks in advance

--
Gerrit Horeis

Software Developer
CI-Gate Development & Consulting GmbH
http://www.ci-gate.de
http://www.xira.de
http://www.bitbauer.de


Mark Fitzpatrick schrieb:

ASP.Net 2.0 could be protecting the memory of the server better.
That's a
400 MB byte array, which for a lot of servers could be 20% of the
available
memory if not more. That could be fine for one and only one user and
page
instance, but what happens if even two users work the code that
requires
a
400 MB byte array allocated. I'm not exactly sure if that's a feasible
array
size for a server environment which could be why it's not letting you
do
it.

Hope this helps,
Mark Fitzpatrick
Microsoft MVP - FrontPage

Hi all,

I'm getting an OutOfMemoryException when I initialize a byte array
in
C# like this:


Byte[] test = new Byte[420000000];


I'm using ASP.NET 2.0. In ASP.Net 1.1 it works fine. So what am I
doing

wrong?

What is the maximum length of a byte array?

Can somebody help me? Thanks in advance!

--
Gerrit Horeis

Software Developer
CI-Gate Development & Consulting GmbH
http://www.ci-gate.de
http://www.xira.de
http://www.bitbauer.de
Click to expand...
Click to expand...
Click to expand...
 
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