Dear experts,

I have recently purchased a workstation (hp xw9300) which is pretty good:
2X Dual core AMD Opteron 285 2.6GHz, 1MB cache
2X 300 GB U320 SCSI 10.000 rpm

In short it is a 2-processor, dual core machine with a total of 600GB memory. (It acts like 4 porocessors.) I have RHEL 4.0 installed on the workstation.

It is a high spec because I use it for scientific work; in particular I compile and run large codes written in FORTRAN, with applications to fluid mechanics type problems -- that means large grid sizes, hence the need for very large memory.

My question relates to fortran compilers. The machine comes installed with with the g77 compiler, which is the standard fortran77 (f77) compiler and that works very nicely and there is no problem.

It also comes witht the gfortran compiler which is the fortran95 (f95) compiler which is slowly replacing f77. I was delighted, but then found much to my annoyance that codes that I rewote in f95 and compiled with gfortran were slower than the f77 version! So I had to go back to the old version.

I have tried to find a suitable f95 compiler for RHEL, but I have been unable to -- there is no official version as far as I can see except for gfortran.

So, my basic question is, can any one help and find a fast f95 compiler suitable for RHEL for me? Are there forums where I can look out for it?

Thank you.

"can any one help and find a fast f95 compiler suitable for RHEL for me?"

I do not think that there is another free f95 compiler available. Intel sells a proprietary f95 compiler which has a free evaluation period.

http://www.intel.com/cd/software/pro...lin/282048.htm

--------------
Steve Stites

I think if you're in academia, the Intel Fortran compiler is free.

Thanks, but is intel fortran compiler compatible with AMD Opteron chip?

Regards

Yes, we have dual Opteron machines at work using it.

That sounds like what I want. Would you be kind enough to specify exactly what is needed, and perhaps the weblink a well?

Thanks.

Try:

http://www.intel.com/cd/software/pro...eng/219771.htm

Click Accept, then scroll down to Compilers, and click on

# Intel® C++ Compiler Professional Edition for Linux*

You then have to register with them to get the download link, if memory serves. Then you just download the tarball, and install it. Can't remember exactly what the install procedure is, but it's not rocket science.

Great -- I have installed the Intel64 fortran compiler successfully. Thanks!

Just a couple of niggly bits:

(1) The instalation guide mentions how to set ip the Compiler Environment

The programs in the Intel Fortran Compiler 10.0 for Linux product rely on the environment variables PATH and LD_LIBRARY_PATH. The installation script (install.sh) creates compiler environment script files (ifortvars.sh/idbvars.sh) that set these variables. It is strongly recommended that you add those script files into your login script (.login file). Once the variables are set in the ".login" file there is no need to run the script files for each session.

source the script to setup the compiler environment:

* > source <install-dir>/bin/ifortvars.sh(.csh)
to use ifort
* > source <idb-install-dir>/bin/idbvars.sh(.csh)
to use idb


However, I cannot find '.login' file in my root directory; but I have the usual files like .bashrc and /etc/login.d and so on. So which is my real login script file where I should add the variables?

The script files are /opt/intel/fce/10.0.023/bin/ifortvars.sh(.csh) Should I add the entire contents of both of these files to the end of my login script file? Or is it enough just to add,

> source /opt/intel/fce/10.0.023/bin/ifortvars.sh

to my login script? (By the way what is the difference between the *.sh and *.csh files?)

(2) If I can be allowed to sneak in an 'ifort' question (its a quicky). With the g77 compiler I use the options: > g77 -Wall -ffast-math -funroll-all-loops -funroll-loops -O3 ......

Does any one know what the best options with the ifort compiler in order to maximmise the speed of vectorising, loop unrollingm i.e. make the executible as fast as possible?

Thanks again.
Cheers

"However, I cannot find '.login' file in my root directory; but I have the usual files like .bashrc and /etc/login.d and so on. So which is my real login script file where I should add the variables?"

Different distributions use different files for login defaults. The files in the root directory are universal defaults which apply to all users. The files appended to user directories apply only to that user. If your distribution uses .bashrc then /home/user/.bashrc contains the local defaults and somewhere in /etc you will find a .bashrc which contains the universal defaults.

"By the way what is the difference between the *.sh and *.csh files?"

You can have several different shells like bash, ksh, etc. .sh is a symbolic link to whichever shell you are using as the default shell. csh is the c shell.

http://en.wikipedia.org/wiki/C_shell

-----------------
Steve Stites

Thanks jailbait. I am using RHEL 4.0 WS. I will put the script into my root /etc/bashrc file since I want all users to be able to access ifort.

So, do I just add the following line at the end of /etc/baschrc :

/opt/intel/fce/10.0.023/bin/ifortvars.sh

?

Regards

"So, do I just add the following line at the end of /etc/baschrc :

/opt/intel/fce/10.0.023/bin/ifortvars.sh"

Yes. Be sure that /opt/intel/fce/10.0.023/bin/ifortvars.sh is executable:

chmod +x /opt/intel/fce/10.0.023/bin/ifortvars.sh

------------------
Steve Stites

Thanks.
(However, I have found that I have to put:
source /opt/intel/fce/10.0.023/bin/ifortvars.sh

in to the /etc/bashrc file ?)

Regards.