diff --git a/README b/README
index 0c57e3f5656268c71bb7732af933302cbde9547b..59c362415a9199d08fb6dfbb1ed044c66e647254 100644
--- a/README
+++ b/README
@@ -23,6 +23,7 @@ Valid options are:
-g Run with an external gravitational potential
-G Run with self-gravity
-s Run with SPH
+ -t {int} The number of threads to use on each MPI rank. Defaults to 1 if not specified.
-v [12] Increase the level of verbosity 1: MPI-rank 0 writes
2: All MPI-ranks write
-y {int} Time-step frequency at which task graphs are dumped
diff --git a/examples/CosmoVolume/cosmoVolume.yml b/examples/CosmoVolume/cosmoVolume.yml
index 20d5febb280748a208633f75351d523b79286035..2da45221043187402bb42028f4d03723cbb26688 100644
--- a/examples/CosmoVolume/cosmoVolume.yml
+++ b/examples/CosmoVolume/cosmoVolume.yml
@@ -9,7 +9,6 @@ UnitSystem:
# Parameters for the task scheduling
Scheduler:
- nr_threads: 16 # The number of threads per MPI rank to use.
nr_queues: 0 # The number of task queues to use. Use 0 to let the system decide.
cell_max_size: 8000000 # Maximal number of interactions per task (this is the default value).
cell_sub_size: 5000 # Maximal number of interactions per sub-task (this is the default value).
diff --git a/examples/CosmoVolume/run.sh b/examples/CosmoVolume/run.sh
index a788a35c76a7c0b205297a7de922a9a7e833243a..412456c3cb1ae9b869afa52b1046747e32c2eefe 100755
--- a/examples/CosmoVolume/run.sh
+++ b/examples/CosmoVolume/run.sh
@@ -7,4 +7,4 @@ then
./getIC.sh
fi
-../swift -s cosmoVolume.yml
+../swift -s -t 16 cosmoVolume.yml
diff --git a/examples/SedovBlast/run.sh b/examples/SedovBlast/run.sh
index 58646cf42eecc3f31fdb8a63ca2108c02d9580ba..f71830eb6a66a9ea84e93fd1bed1261b1cb42b7b 100755
--- a/examples/SedovBlast/run.sh
+++ b/examples/SedovBlast/run.sh
@@ -7,4 +7,4 @@ then
python makeIC_fcc.py
fi
-../swift -s sedov.yml
+../swift -s -t 16 sedov.yml
diff --git a/examples/SedovBlast/sedov.yml b/examples/SedovBlast/sedov.yml
index f354ef5679eb5b6176ab90298bb307c6c2b27f0e..55974b03b823befde8365cddab187f5a18c5bbb7 100644
--- a/examples/SedovBlast/sedov.yml
+++ b/examples/SedovBlast/sedov.yml
@@ -9,7 +9,6 @@ UnitSystem:
# Parameters for the task scheduling
Scheduler:
- nr_threads: 16 # The number of threads per MPI rank to use.
nr_queues: 0 # The number of task queues to use. Use 0 to let the system decide.
cell_max_size: 8000000 # Maximal number of interactions per task (this is the default value).
cell_sub_size: 5000 # Maximal number of interactions per sub-task (this is the default value).
diff --git a/examples/SodShock/run.sh b/examples/SodShock/run.sh
index 646f1e3a337170e2e406c24e7505e42b81de364b..b8141e51543f348d6ec6be505d136aed7d803b2e 100755
--- a/examples/SodShock/run.sh
+++ b/examples/SodShock/run.sh
@@ -7,4 +7,4 @@ then
python makeIC.py
fi
-../swift -s sodShock.yml
+../swift -s -t 16 sodShock.yml
diff --git a/examples/SodShock/sodShock.yml b/examples/SodShock/sodShock.yml
index 5fe7be7b9fc13bb5bc67556d79d8ff9d9eff81d9..ab43d6682b2a16304d364784efee530ad5289cef 100644
--- a/examples/SodShock/sodShock.yml
+++ b/examples/SodShock/sodShock.yml
@@ -9,7 +9,6 @@ UnitSystem:
# Parameters for the task scheduling
Scheduler:
- nr_threads: 16 # The number of threads per MPI rank to use.
nr_queues: 0 # The number of task queues to use. Use 0 to let the system decide.
cell_max_size: 8000000 # Maximal number of interactions per task (this is the default value).
cell_sub_size: 5000 # Maximal number of interactions per sub-task.
diff --git a/examples/UniformBox/run.sh b/examples/UniformBox/run.sh
index ca78b0ac0425bf1b3f6dd9d30bfc95d35083739f..0cb0a505915be47bafb99ed7531685bfeb3dc829 100755
--- a/examples/UniformBox/run.sh
+++ b/examples/UniformBox/run.sh
@@ -7,4 +7,4 @@ then
python makeIC.py 100
fi
-../swift -s uniformBox.yml
+../swift -s -t 16 uniformBox.yml
diff --git a/examples/UniformBox/uniformBox.yml b/examples/UniformBox/uniformBox.yml
index 2d5512815b60511b5dbc373df43fae4658272093..0474b0f8202effa73210ee2b459806f2376a37f2 100644
--- a/examples/UniformBox/uniformBox.yml
+++ b/examples/UniformBox/uniformBox.yml
@@ -9,7 +9,6 @@ UnitSystem:
# Parameters for the task scheduling
Scheduler:
- nr_threads: 16 # The number of threads per MPI rank to use.
nr_queues: 0 # The number of task queues to use. Use 0 to let the system decide.
cell_max_size: 8000000 # Maximal number of interactions per task (this is the default value).
cell_sub_size: 5000 # Maximal number of interactions per sub-task (this is the default value).
diff --git a/examples/main.c b/examples/main.c
index 5cfae5efba9157ba7b727115b03ac467287edc3d..9c98eaf1da6eaacd8ccd31b9b8d8dc6cde6b6f9c 100644
--- a/examples/main.c
+++ b/examples/main.c
@@ -67,6 +67,9 @@ void print_help_message() {
"Run with an external gravitational potential");
printf(" %2s %8s %s\n", "-G", "", "Run with self-gravity");
printf(" %2s %8s %s\n", "-s", "", "Run with SPH");
+ printf(" %2s %8s %s\n", "-t", "{int}",
+ "The number of threads to use on each MPI rank. Defaults to 1 if not "
+ "specified.");
printf(" %2s %8s %s\n", "-v", "[12]",
"Increase the level of verbosity 1: MPI-rank 0 writes ");
printf(" %2s %8s %s\n", "", "", "2: All MPI-ranks write");
@@ -141,12 +144,13 @@ int main(int argc, char *argv[]) {
int with_hydro = 0;
int with_fp_exceptions = 0;
int verbose = 0;
+ int nr_threads = 1;
char paramFileName[200] = "";
unsigned long long cpufreq = 0;
/* Parse the parameters */
int c;
- while ((c = getopt(argc, argv, "cdef:gGhsv:y")) != -1) switch (c) {
+ while ((c = getopt(argc, argv, "cdef:gGhst:v:y")) != -1) switch (c) {
case 'c':
with_cosmology = 1;
break;
@@ -175,6 +179,15 @@ int main(int argc, char *argv[]) {
case 's':
with_hydro = 1;
break;
+ case 't':
+ if (sscanf(optarg, "%d", &nr_threads) != 1) {
+ if (myrank == 0)
+ printf("Error parsing the number of threads (-t).\n");
+ if (myrank == 0) print_help_message();
+ return 1;
+ }
+ with_hydro = 1;
+ break;
case 'v':
if (sscanf(optarg, "%d", &verbose) != 1) {
if (myrank == 0) printf("Error parsing verbosity level (-v).\n");
@@ -383,7 +396,8 @@ int main(int argc, char *argv[]) {
/* Initialize the engine with the space and policies. */
if (myrank == 0) clocks_gettime(&tic);
struct engine e;
- engine_init(&e, &s, params, nr_nodes, myrank, engine_policies, talking);
+ engine_init(&e, &s, params, nr_nodes, myrank, nr_threads, engine_policies,
+ talking);
if (myrank == 0) {
clocks_gettime(&toc);
message("engine_init took %.3f %s.", clocks_diff(&tic, &toc),
diff --git a/examples/parameter_example.yml b/examples/parameter_example.yml
index b91e99baf383a399b72bfb73f1791ab7ac6f3d91..e3cd5b209c9d36f9774364a661b77f3d649c398e 100644
--- a/examples/parameter_example.yml
+++ b/examples/parameter_example.yml
@@ -9,7 +9,6 @@ UnitSystem:
# Parameters for the task scheduling
Scheduler:
- nr_threads: 2 # The number of threads per MPI rank to use.
nr_queues: 0 # The number of task queues to use. Use 0 to let the system decide.
cell_max_size: 8000000 # Maximal number of interactions per task (this is the default value).
cell_sub_size: 8000000 # Maximal number of interactions per sub-task (this is the default value).
diff --git a/src/engine.c b/src/engine.c
index 5e6097981119e6501084335bf966641fabf49db3..7287f47b40b06a691c778a5f8d3b6c0f04721564 100644
--- a/src/engine.c
+++ b/src/engine.c
@@ -2323,20 +2323,21 @@ static bool hyperthreads_present(void) {
* @param params The parsed parameter file.
* @param nr_nodes The number of MPI ranks.
* @param nodeID The MPI rank of this node.
+ * @param nr_threads The number of threads per MPI rank.
* @param policy The queuing policy to use.
* @param verbose Is this #engine talkative ?
*/
void engine_init(struct engine *e, struct space *s,
const struct swift_params *params, int nr_nodes, int nodeID,
- int policy, int verbose) {
+ int nr_threads, int policy, int verbose) {
/* Clean-up everything */
bzero(e, sizeof(struct engine));
/* Store the values. */
e->s = s;
- e->nr_threads = parser_get_param_int(params, "Scheduler:nr_threads");
+ e->nr_threads = nr_threads;
e->policy = policy;
e->step = 0;
e->nr_nodes = nr_nodes;
diff --git a/src/engine.h b/src/engine.h
index e1c3f61d1293fc01e24b9bcb0673d75fa3ce4648..c8b9d7a46f8c788237e3b9ba7cb9d7d0a6e1370d 100644
--- a/src/engine.h
+++ b/src/engine.h
@@ -170,7 +170,7 @@ struct engine {
void engine_barrier(struct engine *e, int tid);
void engine_init(struct engine *e, struct space *s,
const struct swift_params *params, int nr_nodes, int nodeID,
- int policy, int verbose);
+ int nr_threads, int policy, int verbose);
void engine_launch(struct engine *e, int nr_runners, unsigned int mask,
unsigned int submask);
void engine_prepare(struct engine *e);