LoopControl: Update statistics; activate statistics by default

Handle very small grids correctly.
Output statistics all the time.
Introduce multiple verbosity levels for statistics.
Update statistics to include saved time and comparison between best and initial time.
Activate hill climbing algorithm by default.

1 files changed, 38 insertions, 22 deletions

diff --git a/Carpet/LoopControl/src/lc_hill.c b/Carpet/LoopControl/src/lc_hill.c
index 6ab44dba8..362cf8e62 100644
--- a/Carpet/LoopControl/src/lc_hill.c
+++ b/Carpet/LoopControl/src/lc_hill.c
@@ -84,9 +84,9 @@ lc_hill_init (lc_statset_t * restrict const ls,
     return;
   }
   
-  /* If the overhead has become too large, do nothing.  */
+  /* If the overhead has become too large, do nothing. */
   if (ls->time_setup_sum > maximum_setup_overhead * ls->time_calc_sum) {
-    /* Stay at the old state.  */
+    /* Stay at the old state. */
     * new_state = lh->state;
     return;
   }
@@ -120,10 +120,18 @@ lc_hill_init (lc_statset_t * restrict const ls,
       CCTK_INFO ("Hill climbing: Updating best time");
     }
     lh->best_time = lh->time;
+    /* Is there now a better state? */
+    for (lc_stattime_t * lt = ls->stattime_list; lt; lt = lt->next) {
+      double const time = lt->time_calc_sum / lt->time_count;
+      if (time < lh->best_time) {
+        lh->best = lt->state;
+        lh->best_time = time;
+      }
+    }
   }
   
   /* Compare the time for the current state with the time for the
-     previous state.  If the previous state was better, backtrack.  */
+     previous state. If the previous state was better, backtrack. */
   if (lh->have_previous && lh->previous_time < lh->time) {
     if (verbose) {
       CCTK_INFO ("Hill climbing: Backtracking");
@@ -157,7 +165,7 @@ lc_hill_init (lc_statset_t * restrict const ls,
   
  search:;
   
-  /* Look which neighbours exist.  */
+  /* Look which neighbours exist. */
   typedef enum { nb_boundary, nb_missing, nb_exists } neighbour_t;
   neighbour_t  neighbours[3][2];
   lc_state_t   nb_state[3][2];
@@ -194,7 +202,7 @@ lc_hill_init (lc_statset_t * restrict const ls,
   }
   
   /* If not all neighbours exist, then choose a random neighbour and
-     move there.  */
+     move there. */
   if (num_nonexist_states > 0) {
     if (verbose) {
       CCTK_INFO ("Hill climbing: Examining a new state");
@@ -205,32 +213,40 @@ lc_hill_init (lc_statset_t * restrict const ls,
     return;
   }
   
-  /* All neighbours exist.  Look whether we are in a local
-     minimum.  */
+  if (! nb_minimum_time) {
+    /* There are no neighbours. Stay where we are. */
+    if (verbose) {
+      CCTK_INFO ("Hill climbing: No neighbours, staying put");
+    }
+    * new_state = lh->state;
+    return;
+  }
+  
+  /* All neighbours exist. Look whether we are in a local minimum. */
   assert (nb_minimum_time);
   if (minimum_time >= lh->time) {
-    /* We are in a local minimum.  */
+    /* We are in a local minimum. */
     if (verbose) {
       CCTK_INFO ("Hill climbing: Local minimum reached");
     }
     
-    /* Every so often take a small jump.  */
+    /* Every so often take a small jump. */
     if (drand() < probability_small_jump) {
-      /* Be curious, go somewhere nearby.  */
+      /* Be curious, go somewhere nearby. */
       if (verbose) {
         CCTK_INFO ("Hill climbing: Making a small jump");
       }
       for (int ntries = 0; ntries < max_jump_attempts; ++ ntries) {
         lc_state_t try_state = lh->state;
         if (drand() < 0.25) {
-          /* Change the topology, but not the tiling.  */
+          /* Change the topology, but not the tiling. */
           try_state.topology = irand (ls->ntopologies);
           for (int d=0; d<3; ++d) {
             if (try_state.tiling[d] >=
                 ls->topology_ntilings[d][try_state.topology])
             {
               /* The tiling doesn't fit for this new topology; don't
-                 choose this topology.  */
+                 choose this topology. */
               goto next_try;
             }
           }
@@ -252,12 +268,12 @@ lc_hill_init (lc_statset_t * restrict const ls,
         }
       next_try:;
       }
-      /* Don't jump after all.  */
+      /* Don't jump after all. */
     }
     
-    /* Every so often take a random jump.  */
+    /* Every so often take a random jump. */
     if (drand() < probability_random_jump) {
-      /* Be adventurous, go somewhere unknown.  */
+      /* Be adventurous, go somewhere unknown. */
       if (verbose) {
         CCTK_INFO ("Hill climbing: Jumping randomly");
       }
@@ -269,7 +285,7 @@ lc_hill_init (lc_statset_t * restrict const ls,
             irand (ls->topology_ntilings[d][try_state.topology]);
         }
         if (! lc_stattime_find (ls, & try_state)) {
-          /* The new state is hitherto unknown, use it.  */
+          /* The new state is hitherto unknown, use it. */
           lh->state = try_state;
           lh->excursion_start = lh->iteration;
           lh->have_previous = 0; /* disable backtracking */
@@ -277,13 +293,13 @@ lc_hill_init (lc_statset_t * restrict const ls,
           return;
         }
       }
-      /* Don't jump after all.  */
+      /* Don't jump after all. */
     }
     
     /* If the current state is not the best state, give up and go
-       back.  */
+       back. */
     if (! lc_state_equal (& lh->state, & lh->best)) {
-      /* Revert to the best known state.  */
+      /* Revert to the best known state. */
       if (verbose) {
         CCTK_INFO ("Hill climbing: Reverting to best known state");
       }
@@ -294,7 +310,7 @@ lc_hill_init (lc_statset_t * restrict const ls,
       return;
     }
     
-    /* Be content, do nothing.  */
+    /* Be content, do nothing. */
     if (verbose) {
       CCTK_INFO ("Hill climbing: Resting");
     }
@@ -302,8 +318,8 @@ lc_hill_init (lc_statset_t * restrict const ls,
     return;
   }
   
-  /* One of the neighbours is better.  Move to this neighbour, and
-     continue the search there.  */
+  /* One of the neighbours is better. Move to this neighbour, and
+     continue the search there. */
   if (verbose) {
     CCTK_INFO ("Hill climbing: Found a better neighbour, going there");
   }