diff --git a/porting/himax/we2/el_config_porting.h b/porting/himax/we2/el_config_porting.h
index e39d4379..e6467dcf 100644
--- a/porting/himax/we2/el_config_porting.h
+++ b/porting/himax/we2/el_config_porting.h
@@ -44,7 +44,7 @@
     #endif
 #endif
 
-#define CONFIG_EL_DEBUG                4  // use 0 to make firmware generator happy
+#define CONFIG_EL_DEBUG                0  // use 0 to make firmware generator happy
 #define CONFIG_EL_DEBUG_COLOR          0
 #define CONFIG_EL_HAS_FREERTOS_SUPPORT 1
 #define SSCMA_REPL_EXECUTOR_PRIO       2
diff --git a/sscma/callback/invoke.hpp b/sscma/callback/invoke.hpp
index 547b8cd8..e36fb798 100644
--- a/sscma/callback/invoke.hpp
+++ b/sscma/callback/invoke.hpp
@@ -292,11 +292,13 @@ class Invoke final : public std::enable_shared_from_this<Invoke> {
                       static_resource->executor->add_task(
                         [algorithm, cmd = std::move(argv[0]), value, ret, caller](const std::atomic<bool>&) mutable {
                             if (ret == EL_OK) [[likely]] {
-                                algorithm->set_score_threshold(value);
-                                ret = static_resource->storage->emplace(
-                                        el_make_storage_kv_from_type(algorithm->get_algorithm_config()))
-                                        ? EL_OK
-                                        : EL_EIO;
+                                if (algorithm->get_score_threshold() != value) [[likely]] {
+                                    algorithm->set_score_threshold(value);
+                                    ret = static_resource->storage->emplace(
+                                            el_make_storage_kv_from_type(algorithm->get_algorithm_config()))
+                                            ? EL_OK
+                                            : EL_EIO;
+                                }
                             }
                             auto ss{concat_strings("\r{\"type\": 0, \"name\": \"",
                                                    cmd,
@@ -341,11 +343,13 @@ class Invoke final : public std::enable_shared_from_this<Invoke> {
                       static_resource->executor->add_task(
                         [algorithm, cmd = std::move(argv[0]), value, ret, caller](const std::atomic<bool>&) mutable {
                             if (ret == EL_OK) [[likely]] {
-                                algorithm->set_iou_threshold(value);
-                                ret = static_resource->storage->emplace(
-                                        el_make_storage_kv_from_type(algorithm->get_algorithm_config()))
-                                        ? EL_OK
-                                        : EL_EIO;
+                                if (algorithm->get_iou_threshold() != value) [[likely]] {
+                                    algorithm->set_iou_threshold(value);
+                                    ret = static_resource->storage->emplace(
+                                            el_make_storage_kv_from_type(algorithm->get_algorithm_config()))
+                                            ? EL_OK
+                                            : EL_EIO;
+                                }
                             }
                             auto ss{concat_strings("\r{\"type\": 0, \"name\": \"",
                                                    cmd,
diff --git a/sscma/callback/sensor.hpp b/sscma/callback/sensor.hpp
index 6884df23..59b1b4e3 100644
--- a/sscma/callback/sensor.hpp
+++ b/sscma/callback/sensor.hpp
@@ -53,8 +53,9 @@ void set_sensor(
             ret = camera->init(opt_id);  // TODO: custom resolution
             if (ret != EL_OK) [[unlikely]]
                 goto SensorError;
-
+#ifndef CONFIG_EL_BOARD_SENSECAP_WATCHER  // watcher does not store sensor id
             static_resource->storage->emplace(el_make_storage_kv(SSCMA_STORAGE_KEY_CONF_SENSOR_OPT, opt_id));
+#endif
         }
 
         // set the sensor state to available
@@ -65,11 +66,13 @@ void set_sensor(
         // if sensor id changed, update current sensor id
         if (static_resource->current_sensor_id != sensor_id) {
             static_resource->current_sensor_id = sensor_id;
+#ifndef CONFIG_EL_BOARD_SENSECAP_WATCHER  // watcher does not store sensor id
             if (!called_by_event)
                 ret = static_resource->storage->emplace(
                         el_make_storage_kv(SSCMA_STORAGE_KEY_CONF_SENSOR_ID, static_resource->current_sensor_id))
                         ? EL_OK
                         : EL_EIO;
+#endif
         }
     } else
         ret = EL_ENOTSUP;