Compile and run binary black hole GW150914

Download

Download the Cactus tree using the GW150914 thornlist:

curl -O -L https://raw.githubusercontent.com/gridaphobe/CRL/ET_2016_05/GetComponents

chmod a+x GetComponents

./GetComponents --parallel http://einsteintoolkit.org/about/gallery/gw150914/GW150914.th

cd GW150914

Download the parameter file:

        curl -Lf http://einsteintoolkit.org/about/gallery/gw150914/GW150914.rpar -o par/GW150914.rpar

Compile

Configure SimFactory for your machine:

  • If you are on a cluster that SimFactory supports, run
    simfactory/bin/sim setup
    Hit enter for each question if the default is OK. If you intend to run on a cluster that requires an allocation, make sure to configure this during setup.
  • If you are not using a cluster supported by SimFactory, see Compiling the Einstein Toolkit for instructions.

Compile Cactus:

simfactory/bin/sim build --thornlist=thornlists/GW150914.th

Run

Note that the simulation requires about 82 GB of RAM, so most likely you will need to use a cluster. Submit the simulation:

        simfactory/bin/sim create-submit GW150914_28 --define N 28 --parfile par/GW150914.rpar --procs 128 --walltime 24:00:00

You can choose a different number of cores than 128; if it is too small, the simulation will run out of memory.

When the simulation starts running, it will write its output data into GW150914_28 in your simulations directory. You can find the directory containing the output with:

simfactory/bin/sim get-output-dir GW150914_28

You can see the status of the simulation with

simfactory/bin/sim list-simulations GW150914_28

for example

GW150914_28             [ACTIVE (RUNNING), restart 0000, job id 363502]

It will say FINISHED when the simulation has finished. You can check the output while it is still running.

Output

You can see the console output of the simulation in

/path/to/GW150914_28/output-0000/GW150914_28.out

for example:

Simulation name: GW150914_28
Running simulation GW150914_28

       10                                  
  1   0101       ************************  
  01  1010 10      The Cactus Code V4.3.0    
 1010 1101 011      www.cactuscode.org     
  1001 100101    ************************  
    00010101                               
     100011     (c) Copyright The Authors  
      0100      GNU Licensed. No Warranty  
      0101                                 
--------------------------------------------------------------------------------

Cactus version:    4.3.0
...
----------------------------------------------------------------------------------------------------------
Iteration      Time | *me_per_hour |              ML_BSSN::phi | *TISTICS::maxrss_mb | *TICS::swap_used_mb
                    |              |      minimum      maximum |   minimum   maximum |   minimum   maximum
----------------------------------------------------------------------------------------------------------
        0     0.000 |    0.0000000 |    0.0005741    0.9995490 |      2580      3510 |         0         0
        4     0.009 |    3.0212222 |    0.0005853    0.9995490 |      2781      3811 |         0         0
        8     0.017 |    5.5436288 |    0.0005960    0.9995490 |      2781      3811 |         0         0
       12     0.026 |    7.4708510 |    0.0006063    0.9995490 |      2781      3811 |         0         0
       16     0.034 |    9.2093008 |    0.0006161    0.9995490 |      2781      3811 |         0         0
...

Visualise

You can do a quick-and-dirty visualisation of the coordinate tracks of the black holes with gnuplot:

cd /path/to/GW150914_28/output-0000/GW150914_28
gnuplot

set size square 0.75,0.75
set key
plot 'puncturetracker-pt_loc..asc' u 23:33 title "BH 1", 'puncturetracker-pt_loc..asc' u 24:34 title "BH 2"
BH trajectories