32bits virtual addressing and Memory Windows

[Takeshi Sugai]

Hi, All.

According to Memory Windows White Paper said:
Without Memory Windows, 32-bits API of Program Data is limited to 1 Gigabyte.
I would like to know that how much Program Data limitation on L-class, HP-UX 11.00 and 32 bites API.
1 Gigabyte or 2 Gigabyte ?
I believe that 2 Gigabytes is limitation, if we set maxdsiz parameter to 2 Gigabyte.

And is it true that each process can get maximum of 2 Gigabytes if we set maxdsiz parameters to 2 Gigabyte.
For example, we have 6 Gigabyte RAM,
Each 3 process can get 2 Giagabyte. right?
Thanks for any help...

[CHRIS ANORUO]

Hi Takeshi,

That assumption is very very wrong. Have a look at the following:

http://www.docs.hp.com/hpux/content/KCparams.OverviewAll.html

[Stefan Farrelly]

Theres a good summary of this already;

http://my1.itrc.hp.com/cm/QuestionAnswer/1,1150,0x5694c3d7fb78d4118fef0090279cd0f9,00.html

Look for the answer that got 10 points.

[Takeshi Sugai]

Hi,Chris.

You mean that the balance is important like memory allocation management maxtsiz, maxssiz,maxdsiz?

Could you elaborate what you refered to the very wrong.

I would like to confirm that we can use 2 Gigabyte not 1 Gigabyte on HP-UX 11.00, L-Class for 32-bits API.
Any tips would be appreciated.

[Andy Monks]

On a per process bases, you can get close to 2GB. Your executables need to be compiled with the EXEC_MAGIC flag. Then the data segment, begins just above the executable, rather then at the 1GB point which is the norm. Then, as the stack grows down, the maximum for data is limited by, executable size and stack size max (and a couple of smaller bits like uarea etc). But 1.9GB is possible. This has nothing to do with memory windows.

Memory windows is really for shared memory. From what you've said, it doesn't appear your using shared memory, and therefore memory windows won't help.

Andy

[Takeshi Sugai]

Hi Andy,
Do you know that how to analize excutable file is
with linked the EXEC_MAGIC option or not.

Any command ?

[CHRIS ANORUO]

Hi Takeshi,

I hope Andy has answered that question. Check out Stefan's link to see if it will help you out. (***And Award Your marks***)

[Stefan Farrelly]

use chatr on the binary to see if is using EXEC_MAGIC or SHMEM_MAGIC (see man on chatr)

[CHRIS ANORUO]

Hi Takeshi,

I hope Andy has answered that question. Check out Stefan's link to see if it will help you out. (***And Award Your marks***)

[Andy Monks]

use the 'chatr' command.

It will say :-

'shared executable' for shared_magic

and

'normal executable' for exec_magic

shared executable is the default.