engine: reduce sysfs writes

src/engine.rs

@@ -420,13 +420,25 @@ fn manage_auto_turbo(
         hysteresis.update_state(enable_turbo);
     }
 
-    // Apply the turbo setting
+    // Only apply the setting if the state has changed
+    let changed = previous_turbo_enabled != enable_turbo;
+    if changed {
         let turbo_setting = if enable_turbo {
             TurboSetting::Always
         } else {
             TurboSetting::Never
         };
 
+        info!(
+            "Auto Turbo: Applying turbo change from {} to {}",
+            if previous_turbo_enabled {
+                "enabled"
+            } else {
+                "disabled"
+            },
+            if enable_turbo { "enabled" } else { "disabled" }
+        );
+
         match cpu::set_turbo(turbo_setting) {
             Ok(()) => {
                 debug!(
@@ -437,6 +449,13 @@ fn manage_auto_turbo(
             }
             Err(e) => Err(EngineError::ControlError(e)),
         }
+    } else {
+        debug!(
+            "Auto Turbo: Maintaining turbo state ({}) - no change needed",
+            if enable_turbo { "enabled" } else { "disabled" }
+        );
+        Ok(())
+    }
 }
 
 fn validate_turbo_auto_settings(settings: &TurboAutoSettings) -> Result<(), EngineError> {