ignore first kernel call in benchmarks

1 files changed, 8 insertions, 2 deletions

diff --git a/benchmark.py b/benchmark.py
index 0f72811..441b85f 100644
--- a/benchmark.py
+++ b/benchmark.py
@@ -55,7 +55,10 @@ def ray_trace(gpu, number=1000):
         gpu.kernels.ray_trace(np.int32(pixels_gpu.size), origins_gpu, directions_gpu, pixels_gpu, block=(gpu.nthreads_per_block,1,1), grid=(pixels_gpu.size//gpu.nthreads_per_block+1,1))
         gpu.context.synchronize()
         elapsed = time.time() - t0
-        run_times.append(elapsed)
+
+        if i > 0:
+            # first kernel call incurs some driver overhead
+            run_times.append(elapsed)
 
     return pixels_gpu.size/ufloat((np.mean(run_times),np.std(run_times)))
 
@@ -82,7 +85,10 @@ def propagate(gpu, number=10, nphotons=500000):
         gpu.propagate()
         gpu.context.synchronize()
         elapsed = time.time() - t0
-        run_times.append(elapsed)
+
+        if i > 0:
+            # first kernel call incurs some driver overhead
+            run_times.append(elapsed)
 
     return nphotons/ufloat((np.mean(run_times),np.std(run_times)))