Merge pull request #200 from prabhuramachandran/change-cache-nnps-dyn…

…amically

Allow user to set the caching dynamically ...

pysph/base/gpu_nnps_base.pyx

@@ -221,6 +221,12 @@ cdef class GPUNNPS(NNPSBase):
         self.particles[pa_index].gpu.align(indices)
         callback()
 
+    def set_use_cache(self, bint use_cache):
+        self.use_cache = use_cache
+        if use_cache:
+            for cache in self.cache:
+                cache.update()
+
     cdef void find_neighbor_lengths(self, nbr_lengths):
         raise NotImplementedError("NNPS :: find_neighbor_lengths called")
 

pysph/base/nnps_base.pxd

@@ -265,7 +265,7 @@ cdef class NNPSBase:
     cdef public list particles        # list of particle arrays
     cdef public list pa_wrappers      # list of particle array wrappers
     cdef public int narrays           # Number of particle arrays
-    cdef public bint use_cache        # Use cache or not.
+    cdef bint use_cache               # Use cache or not.
     cdef public list cache            # The neighbor cache.
     cdef int src_index, dst_index     # The current source and dest indices
 

pysph/base/nnps_base.pyx

@@ -1238,6 +1238,12 @@ cdef class NNPS(NNPSBase):
     def set_in_parallel(self, bint in_parallel):
         self.domain.manager.in_parallel = in_parallel
 
+    def set_use_cache(self, bint use_cache):
+        self.use_cache = use_cache
+        if use_cache:
+            for cache in self.cache:
+                cache.update()
+
     def update_domain(self):
         self.domain.update()
 

pysph/base/tests/test_neighbor_cache.py

@@ -90,6 +90,31 @@ def test_cache_updates_with_changed_particles(self):
             nb_c = nb_cached.get_npy_array()
             self.assertTrue(np.all(nb_e == nb_c))
 
+    def test_setting_use_cache_does_cache(self):
+        # Given
+        pa = self._make_random_parray('pa1', 3)
+        pa.h[:] = 1.0
+        nnps = LinkedListNNPS(dim=3, particles=[pa], cache=False)
+        n = pa.get_number_of_particles()
+
+        # When
+        nnps.set_use_cache(True)
+        nbrs = UIntArray()
+        nnps.set_context(0, 0)
+        for i in range(n):
+            nnps.get_nearest_particles(0, 0, i, nbrs)
+
+        # Then
+        self.assertEqual(nbrs.length, n)
+        # Find the length of all cached neighbors,
+        # in this case, each particle has n neighbors,
+        # so we should have n*n neighbors in all.
+        total_length = sum(
+            x.length for x in nnps.cache[0]._neighbor_arrays
+        )
+        self.assertEqual(total_length, n*n)
+
+
 
 if __name__ == '__main__':
     unittest.main()

pysph/solver/application.py

@@ -221,6 +221,9 @@ def __init__(self, fname=None, domain=None):
         self.output_dir = abspath(self._get_output_dir_from_fname())
         self.particles = []
         self.inlet_outlet = []
+        # The default value that is overridden by the command line
+        # options passed or in initializee.
+        self.cache_nnps = False
 
         self.initialize()
         self.scheme = self.create_scheme()
@@ -577,7 +580,7 @@ def _setup_argparse(self):
             "--cache-nnps",
             dest="cache_nnps",
             action="store_true",
-            default=False,
+            default=self.cache_nnps,
             help="Option to enable the use of neighbor caching.")
 
         nnps_options.add_argument(
@@ -908,20 +911,21 @@ def _create_particles(self, particle_factory, *args, **kw):
     def _configure_options(self):
         options = self.options
         # Setup configuration options.
+        config = get_config()
         if options.with_openmp is not None:
-            get_config().use_openmp = options.with_openmp
+            config.use_openmp = options.with_openmp
         if options.omp_schedule is not None:
-            get_config().set_omp_schedule(options.omp_schedule)
+            config.set_omp_schedule(options.omp_schedule)
         if options.with_opencl:
-            get_config().use_opencl = True
+            config.use_opencl = True
         if options.with_local_memory:
             leaf_size = int(options.octree_leaf_size)
-            get_config().wgs = leaf_size
-            get_config().use_local_memory = True
+            config.wgs = leaf_size
+            config.use_local_memory = True
         if options.use_double:
-            get_config().use_double = options.use_double
+            config.use_double = options.use_double
         if options.profile:
-            get_config().profile = options.profile
+            config.profile = options.profile
         for pa in self.particles:
             pa.update_backend()