Make search window a program parameter

Testing only

examples/main.c

@@ -85,6 +85,7 @@ int main(int argc, char *argv[]) {
   int nr_nodes = 1, myrank = 0, grid[3] = {1, 1, 1};
   FILE *file_thread;
   int with_outputs = 1;
+  int queue_search_window = 8;
 
 /* Choke on FP-exceptions. */
 // feenableexcept( FE_DIVBYZERO | FE_INVALID | FE_OVERFLOW );
@@ -135,7 +136,7 @@ int main(int argc, char *argv[]) {
   bzero(&s, sizeof(struct space));
 
   /* Parse the options */
-  while ((c = getopt(argc, argv, "a:c:d:f:g:m:q:r:s:t:w:y:z:")) != -1)
+  while ((c = getopt(argc, argv, "a:c:d:f:g:m:o:q:r:s:t:v:w:y:z:")) != -1)
     switch (c) {
       case 'a':
         if (sscanf(optarg, "%lf", &scaling) != 1)
@@ -193,6 +194,12 @@ int main(int argc, char *argv[]) {
           error("Error parsing sub size.");
         if (myrank == 0) message("sub size set to %i.", space_subsize);
         break;
+      case 'v':
+        if (sscanf(optarg, "%d", &queue_search_window) != 1)
+          error("Error parsing sub size.");
+        if (myrank == 0) message("task overlap search window set to %i.", 
+                                 queue_search_window);
+        break;
       case 'y':
         if(sscanf(optarg, "%d", &dump_tasks) != 1)
           error("Error parsing dump_tasks (-y)");
@@ -335,7 +342,7 @@ int main(int argc, char *argv[]) {
   tic = getticks();
   if (myrank == 0) message("nr_nodes is %i.", nr_nodes);
   engine_init(&e, &s, dt_max, nr_threads, nr_queues, nr_nodes, myrank,
-              ENGINE_POLICY | engine_policy_steal);
+              ENGINE_POLICY | engine_policy_steal, queue_search_window);
   if (myrank == 0)
     message("engine_init took %.3f ms.",
             ((double)(getticks() - tic)) / CPU_TPS * 1000);

src/engine.c

@@ -2150,10 +2150,13 @@ static bool hyperthreads_present(void) {
  * @param nr_nodes The number of MPI ranks
  * @param nodeID The MPI rank of this node
  * @param policy The queuing policy to use.
+ * @param queue_search_window the search window for overlapping tasks.
  */
 
 void engine_init(struct engine *e, struct space *s, float dt, int nr_threads,
-                 int nr_queues, int nr_nodes, int nodeID, int policy) {
+                 int nr_queues, int nr_nodes, int nodeID, int policy,
+                 int queue_search_window) {
+
 
   int i, k;
   float dt_min = dt;
@@ -2237,6 +2240,7 @@ void engine_init(struct engine *e, struct space *s, float dt, int nr_threads,
   e->forcerepart = 0;
   e->links = NULL;
   e->nr_links = 0;
+  e->queue_search_window = queue_search_window;
   engine_rank = nodeID;
 
   /* Make the space link back to the engine. */

src/engine.h

@@ -54,6 +54,7 @@
 #define engine_maxtaskspercell 128
 #define engine_maxproxies 64
 #define engine_tasksreweight 10
+#define engine_queue_search_window 8
 
 #define engine_maxmetisweight 10000.0f
 
@@ -134,6 +135,9 @@ struct engine {
   struct link *links;
   int nr_links, size_links;
 
+  /* Search window for overlapping tasks. */
+  int queue_search_window;
+
 #ifdef WITH_MPI
   /* MPI data type for the particle transfers */
   MPI_Datatype part_mpi_type;
@@ -144,7 +148,8 @@ struct engine {
 /* Function prototypes. */
 void engine_barrier(struct engine *e, int tid);
 void engine_init(struct engine *e, struct space *s, float dt, int nr_threads,
-                 int nr_queues, int nr_nodes, int nodeID, int policy);
+                 int nr_queues, int nr_nodes, int nodeID, int policy,
+                 int queue_search_window);
 void engine_launch(struct engine *e, int nr_runners, unsigned int mask);
 void engine_prepare(struct engine *e);
 void engine_step(struct engine *e);

src/queue.c

@@ -130,7 +130,8 @@ void queue_init(struct queue *q, struct task *tasks) {
  * @param blocking Block until access to the queue is granted.
  */
 
-struct task *queue_gettask(struct queue *q, const struct task *prev, int blocking) {
+struct task *queue_gettask(struct queue *q, const struct task *prev, 
+                           int blocking, int queue_search_window) {
 
   lock_type *qlock = &q->lock;
   struct task *res = NULL;

src/queue.h

@@ -28,7 +28,6 @@
 #define queue_maxsuper 50
 #define queue_sizeinit 100
 #define queue_sizegrow 2
-#define queue_search_window 8
 
 /* Counters. */
 enum {
@@ -55,7 +54,8 @@ struct queue {
 } __attribute__((aligned(64)));
 
 /* Function prototypes. */
-struct task *queue_gettask(struct queue *q, const struct task *prev, int blocking);
+struct task *queue_gettask(struct queue *q, const struct task *prev, 
+                           int blocking, int queue_search_window);
 void queue_init(struct queue *q, struct task *tasks);
 void queue_insert(struct queue *q, struct task *t);
 

src/runner.c

@@ -1198,7 +1198,7 @@ void *runner_main(void *data) {
 
         /* Get the task. */
         TIMER_TIC
-        t = scheduler_gettask(sched, r->qid, prev);
+            t = scheduler_gettask(sched, r->qid, prev, e->queue_search_window);
         TIMER_TOC(timer_gettask);
 
         /* Did I get anything? */

src/scheduler.c

@@ -1066,8 +1066,8 @@ void scheduler_enqueue(struct scheduler *s, struct task *t) {
         break;
       case task_type_send:
 #ifdef WITH_MPI
-        if ((err = MPI_Isend(t->ci->parts, t->ci->count, s->part_mpi_type, 
-			     t->cj->nodeID, t->flags, MPI_COMM_WORLD, 
+        if ((err = MPI_Isend(t->ci->parts, t->ci->count, s->part_mpi_type,
+			     t->cj->nodeID, t->flags, MPI_COMM_WORLD,
 			     &t->req)) != MPI_SUCCESS) {
           char buff[MPI_MAX_ERROR_STRING];
           int len;
@@ -1186,12 +1186,14 @@ struct task *scheduler_unlock(struct scheduler *s, struct task *t) {
  * @param s The #scheduler.
  * @param qid The ID of the preferred #queue.
  * @param prev the previous task that was run.
+ * @param queue_search_window window to search for overlapping tasks.
  *
  * @return A pointer to a #task or @c NULL if there are no available tasks.
  */
 
 struct task *scheduler_gettask(struct scheduler *s, int qid,
-                               const struct task *prev) {
+                               const struct task *prev,
+                               int queue_search_window) {
 
   struct task *res = NULL;
   int k, nr_queues = s->nr_queues;
@@ -1210,7 +1212,7 @@ struct task *scheduler_gettask(struct scheduler *s, int qid,
       /* Try to get a task from the suggested queue. */
       if (s->queues[qid].count > 0) {
         TIMER_TIC
-        res = queue_gettask(&s->queues[qid], prev, 0);
+            res = queue_gettask(&s->queues[qid], prev, 0, queue_search_window);
         TIMER_TOC(timer_qget);
         if (res != NULL) break;
       }
@@ -1223,7 +1225,8 @@ struct task *scheduler_gettask(struct scheduler *s, int qid,
         for (k = 0; k < scheduler_maxsteal && count > 0; k++) {
           int ind = rand_r(&seed) % count;
           TIMER_TIC
-          res = queue_gettask(&s->queues[qids[ind]], prev, 0);
+              res = queue_gettask(&s->queues[qids[ind]], prev, 0,
+                                  queue_search_window);
           TIMER_TOC(timer_qsteal);
           if (res != NULL)
             break;

src/scheduler.h

@@ -109,7 +109,8 @@ struct scheduler {
 void scheduler_init(struct scheduler *s, struct space *space, int nr_tasks,
                     int nr_queues, unsigned int flags, int nodeID);
 struct task *scheduler_gettask(struct scheduler *s, int qid,
-                               const struct task* prev);
+                               const struct task* prev, 
+                               int queue_search_window);
 void scheduler_enqueue(struct scheduler *s, struct task *t);
 void scheduler_start(struct scheduler *s, unsigned int mask);
 void scheduler_reset(struct scheduler *s, int nr_tasks);