I have already posted on Java groups:

I am trying to execute a Java program with -Xmx2700m it fails on
gentoo. the max i can set is -Xmx2650m.

But if I am able to set much larger values on Fedora linux.
We are using same jdk1.5.0 on both systems. any pointers please?
--------------------------------------------
Following is the Test.java program on gentoo:

public class Test
{
public static void main(String[] args)
{
System.out.println("Hello World");
}
}

# Java -Xmx2700m Test                                          ~
Error occurred during initialization of VM
Could not reserve enough space for object heap
Could not create the Java virtual machine.
# uname -a                                                 ~
Linux linux6 2.6.12-gentoo-r6 #1 SMP

On Fedora Core 3:
------------------
# uname -a
Linux linux7 2.6.9-1.667 #1

# Java -Xmx2900m Test
Hello World


TIA
Ravi KAtti

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ravikatti@gmail.com said:
>I have already posted on Java groups:
>
>I am trying to execute a Java program with -Xmx2700m it fails on
>gentoo. the max i can set is -Xmx2650m.
>
>But if I am able to set much larger values on Fedora linux.
>We are using same jdk1.5.0 on both systems. any pointers please?

Could be that the kernel on gentoo is compiled with a different
memory model than that on Fedora.
--
Wolf  a.k.a.  Juha Laiho     Espoo, Finland
(GC 3.0) GIT d- s+: a C++ ULSH++++$ P++@ L+++ E- W+$@ N++ !K w !O !M V
PS(+) PE Y+ PGP(+) t- 5 !X R !tv b+ !DI D G e+ h---- r+++ y++++
"...cancel my subscription to the resurrection!" (Jim Morrison)

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Juha Laiho wrote:

> ravikatti@gmail.com said: 
>
> Could be that the kernel on gentoo is compiled with a different
> memory model than that on Fedora.
> --
> Wolf  a.k.a.  Juha Laiho     Espoo, Finland
> (GC 3.0) GIT d- s+: a C++ ULSH++++$ P++@ L+++ E- W+$@ N++ !K w !O !M V
>          PS(+) PE Y+ PGP(+) t- 5 !X R !tv b+ !DI D G e+ h---- r+++ y++++
> "...cancel my subscription to the resurrection!" (Jim Morrison)

Hey thanks for the reply. Its all about allocating contiguous memory.
Any kernel tweaks that can be helpful?

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In comp.unix.admin ravikatti@gmail.com:
> I have already posted on Java groups:

> I am trying to execute a Java program with -Xmx2700m it fails on
> gentoo. the max i can set is -Xmx2650m.

> But if I am able to set much larger values on Fedora linux.
> We are using same jdk1.5.0 on both systems. any pointers please?
[..]

> # Java -Xmx2700m Test                                          ~
> Error occurred during initialization of VM
> Could not reserve enough space for object heap

Try raising (needs root permissions) the maximum data segment
size ('ulimit -d <nnn>') and see if this works better. Check the
working box settings and use this as start.

[..]

Good luck

--
Michael Heiming (X-PGP-Sig > GPG-Key ID: EDD27B94)
mail: echo zvpunry@urvzvat.qr | PERL -pe 'y/a-z/n-za-m/'
#bofh excuse 109: The electricity substation in the car park
blew up.

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