Very Computer

Someone started a thread with this very appropriate subject. But I
did not see any relevant answers to the topic. So let me raise
it again. We are about the by a really big Alpha server with some 3GB
of RAM  and 40 or so GB of disk space. What are our chances of
being able to handle files larger than 2GB?

This will certainly be a requirement if Linux is to make inroads in
high end computing.

greetings

Eildert Groeneveld
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Hello there.

Linux cannot handle files larger than that at the present time, as of my
knowledge.

Quote:> This will certainly be a requirement if Linux is to make inroads in
> high end computing.

Linux made it a long time ago.

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  ______O___
  \________/   Igor Zlatkovic

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      ||       University of Applied Sciences
   ___||___    Frankfurt, Germany, EU.

I've heard that Linux can handle files larger than 2Gb on 64 bit
machines, such as Alpha.
Eugene

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Homepage: http://lucifer.dorms.spbu.ru     conversations with God)."
                                           (By Matt Welsh)

You mention Intel in the Subject, then Alpha in the body.
Linux is 64 bit on 64 bit architectures (Alpha, UltraSparc) so you
will have no problems having files >2GB on an AlphaServer.

There are several issues.  First is the filesystems themselves:

- ext2fs in linux-2.2 supports files bigger than 2GB (up to 1TB for
  filesystems with sufficiently big blocks (the limit comes from the
  triple-indirect blocks)).
- NFS only supports 32bits.
- NFSv3 supports 64bits (NFSv3 is available as a patch to the standard
  distribution).
- ...

Then, there is the interface between the user-code and the filesystem code:
On Linux-2.0, there is no support for more than 2GB files.
On Linux-2.2, files bigger than 2GB are supported but only on 64bit
architectures (alpha, Sparc64, ...).  So on Intel, you're out of luck.
But there is a patch (in alpha or beta quality, I don't know) for linux-2.2
that adds support for 64bit filesize on 32bit architectures (such as x86).
The catch is that any program that wants to access such a large file needs
recompilation.

        Stefan

Quote:> Someone started a thread with this very appropriate subject. But I
> did not see any relevant answers to the topic. So let me raise
> it again. We are about the by a really big Alpha server with some 3GB
> of RAM  and 40 or so GB of disk space. What are our chances of
> being able to handle files larger than 2GB?

This has been discussed to death numerous times already. Please check
dejanews.

The short answer:
- for 64 bit architectures files larger than 2GB are supported already
- for 32 bit architectures there is no way to add support unless you do
major modifications to the kernel as well as to core libraries as well as
(in consequence to the library changes) to most applications.

jue
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Jrgen Exner