diff --git a/src/base/integrator.h b/src/base/integrator.h
index 631c41c4..be446c9e 100644
--- a/src/base/integrator.h
+++ b/src/base/integrator.h
@@ -112,8 +112,8 @@ class DifferentiableIntegrator : public Integrator {
     };
 
 private:
-    luisa::unique_ptr<Loss> _loss;
-    luisa::unique_ptr<Optimizer> _optimizer;
+    const Loss *_loss;
+    const Optimizer *_optimizer;
     uint _iterations;
     int _display_camera_index;
     bool _save_process;
@@ -122,8 +122,8 @@ class DifferentiableIntegrator : public Integrator {
     DifferentiableIntegrator(Scene *scene, const SceneNodeDesc *desc) noexcept;
 
     [[nodiscard]] bool is_differentiable() const noexcept override { return true; }
-    [[nodiscard]] auto loss() const noexcept { return _loss.get(); }
-    [[nodiscard]] auto optimizer() const noexcept { return _optimizer.get(); }
+    [[nodiscard]] auto loss() const noexcept { return _loss; }
+    [[nodiscard]] auto optimizer() const noexcept { return _optimizer; }
     [[nodiscard]] auto iterations() const noexcept { return _iterations; }
     [[nodiscard]] int display_camera_index() const noexcept { return _display_camera_index; }
     [[nodiscard]] bool save_process() const noexcept { return _save_process; }
diff --git a/src/textures/constant.cpp b/src/textures/constant.cpp
index f5a02e21..1cc9d92b 100644
--- a/src/textures/constant.cpp
+++ b/src/textures/constant.cpp
@@ -68,7 +68,6 @@ class ConstantTextureInstance final : public Texture::Instance {
                             CommandBuffer &cmd_buffer,
                             luisa::optional<Differentiation::ConstantParameter> param) noexcept
         : Texture::Instance{p, t}, _diff_param{std::move(param)} {
-        LUISA_INFO("index {} prepared.", _diff_param->index());
         if (!t->should_inline()) {
             auto [buffer, buffer_id] = p.allocate_constant_slot();
             auto v = t->v();
@@ -104,8 +103,8 @@ class ConstantTextureInstance final : public Texture::Instance {
                   Expr<float>, Expr<float4> grad) const noexcept override {
         if (_diff_param) {
             $if(_diff_param->index() != 0u) {
-                device_log("ggggggggg ({}) , grad in accumulate: ({}, {}, {})",
-                           _diff_param->index(), grad[0u], grad[1u], grad[2u]);
+                // device_log("ggggggggg ({}) , grad in accumulate: ({}, {}, {})",
+                //            _diff_param->index(), grad[0u], grad[1u], grad[2u]);
             };
             auto slot_seed = xxhash32(as<uint3>(it.p()));
             // $if(_diff_param->index() == 1u) {