= Basic installations instructions =

== Installation of iLOVECLIM on obelix (LSCE)==

To install iloveclim, open a terminal, go to the chosen directory, and type:

* To get the iLOVECLIM code with svn:[[BR]]
{{{ 
svn co svn+ssh://forge.ipsl.jussieu.fr/ipsl/forge/projets/ludus/svn/trunk iloveclim/.
}}}

* To load the modules:[[BR]]
{{{ 
module load netcdf
}}}
{{{
module load udunits
}}}

* To install everything:
{{{
./install_ludus.sh 
}}}

You can then start the test run:
{{{
./bin/loveclim-new-run
}}}

If everything is ok it should have run.

== Running iLOVECLIM ==

    To start a run:

nohup ./bin/loveclim-new-run -l LH -n 500 -r 250 > run_LH &

starts a simulation called LH which lasts 500 years and writes restart files every 250 years, starting from the default initial conditions.

    To see more options:

./bin/loveclim-new-run -h

== OpenMP ==

As of version 758, there is a possibility to run with OpenMP activated. Just use the "-p" switch in the call e.g.: 
{{{
./binloveclim-new-run -l LH -n 500 -r 250 -p
}}}
this will by default use all cores available on the given machine. [[BR]]

The expected performance increase is of about 40-50% on 4 cores, slightly more with carbon cycle activated, at time of writing (2017-11-30). [[BR]]
An example of the comparative performance is displayed below:

[[Image(Screenshot_2017-12-13_15-40-33.png)]]