diff --git a/ci/scripts/test.sh b/ci/scripts/test.sh
index 51b8b970edfa87e2a54dd06852ff62fe867a1cca..f25d5a2bb455ff32d94d269955cb3b57572cdc94 100755
--- a/ci/scripts/test.sh
+++ b/ci/scripts/test.sh
@@ -52,15 +52,15 @@ python -c 'import hysop; print hysop'
 #python "$HYSOP_DIR/backend/device/codegen/kernels/tests/test_directional_advection.py"
 #python "$HYSOP_DIR/backend/device/codegen/kernels/tests/test_directional_remesh.py"
 
-python "$HYSOP_DIR/core/arrays/tests/test_array.py"
-python "$HYSOP_DIR/core/graph/tests/test_graph.py"
-python "$HYSOP_DIR/fields/tests/test_fields.py"
-$HYSOP_DIR/fields/tests/test_cartesian.sh
-python "$HYSOP_DIR/numerics/tests/test_fft.py"
-python "$HYSOP_DIR/operator/tests/test_analytic.py"
-python "$HYSOP_DIR/operator/tests/test_transpose.py"
-python "$HYSOP_DIR/operator/tests/test_fd_derivative.py"
-python "$HYSOP_DIR/operator/tests/test_absorption.py"
+#python "$HYSOP_DIR/core/arrays/tests/test_array.py"
+#python "$HYSOP_DIR/core/graph/tests/test_graph.py"
+#python "$HYSOP_DIR/fields/tests/test_fields.py"
+#$HYSOP_DIR/fields/tests/test_cartesian.sh
+#python "$HYSOP_DIR/numerics/tests/test_fft.py"
+#python "$HYSOP_DIR/operator/tests/test_analytic.py"
+#python "$HYSOP_DIR/operator/tests/test_transpose.py"
+#python "$HYSOP_DIR/operator/tests/test_fd_derivative.py"
+#python "$HYSOP_DIR/operator/tests/test_absorption.py"
 python "$HYSOP_DIR/operator/tests/test_directional_advection.py"
 python "$HYSOP_DIR/operator/tests/test_directional_diffusion.py"
 python "$HYSOP_DIR/operator/tests/test_directional_stretching.py"
diff --git a/hysop/backend/device/codegen/kernels/directional_advection.py b/hysop/backend/device/codegen/kernels/directional_advection.py
index 594380a69959ee77533cf505393be273e3544ea2..c364732e1ff271df378bf49b03ace69c17564f3d 100644
--- a/hysop/backend/device/codegen/kernels/directional_advection.py
+++ b/hysop/backend/device/codegen/kernels/directional_advection.py
@@ -590,8 +590,9 @@ class DirectionalAdvectionKernelGenerator(KernelCodeGenerator):
                                 i='idx', N=V_cache_width, 
                                 Lx=local_id[0], gsize=local_size[0])
                         with s._for_(loop):
-                            code='{dst}[{i}] = 0.0;'.format(i='idx', dst=Vc)
+                            code='{dst}[{i}] = 0.5;'.format(i='idx', dst=Vc)
                             s.append(code)
+                        s.barrier(_local=True)
                     else:
                         code='event_t event = async_work_group_copy({dst}, {src}, {ne}, {event});'.format(
                                 dst=Vc, src=line_velocity, ne=V_cache_width, event=0)
diff --git a/hysop/numerics/fft/gpyfft_fft.py b/hysop/numerics/fft/gpyfft_fft.py
index 3fb175c4164b1db258e0b6dd4bcf9412c2e31b1c..341a449fc614670874cc635047dd2c4b79905542 100644
--- a/hysop/numerics/fft/gpyfft_fft.py
+++ b/hysop/numerics/fft/gpyfft_fft.py
@@ -1250,6 +1250,10 @@ class GpyFFT(OpenClFFTI):
         - real planning capability (but no explicit caching capabilities)
         - injection of custom opencl code for pre and post processing.
 
+    It also has some disadvantages:
+        - Bad OpenCL CPU devices support
+        - The library is to greedy with temporary buffers for big transforms.
+
     Planning may destroy initial arrays content.
     Executing a plan may result in unwanted writes to output data, see notes.