Owners of Xiaomi smartphones, in particular the Redmi Note 9 model, often face intrusive MIUI optimization system. Aggressive memory management leads to the fact that background applications such as messengers or navigators are unexpectedly closed, which causes the loss of important notifications and interruption of active tasks.
Android's MIUI shell is designed to save the battery as much as possible, so it compulsorily completes processes it considers inactive, but for many users it is critical that certain programs run all the time, and the solution is to manually configure exceptions.
In this article, we will detail how to prevent your system from unloading the applications you want from RAM, learn how to set up auto-start and fix processes in Task Manager, which will allow your Redmi Note 9 to work exactly as you require, rather than energy saving algorithms.
The principle of operation of the MIUI memory optimizer
The MIUI shell uses its own resource management mechanism, which is different from standard Android. The system constantly monitors the load on the processor and the amount of free RAM. When free space ends or the power saving mode is turned on, the optimizer begins to force the background processes to close.
Users often don’t understand why an app stops sending messages or resets motion tracking, because the system considers the program “heavy” or “rarely used.” Without manually configuring exceptions, the Redmi Note 9 will behave in this way with many services.
⚠️ Warning: A complete shutdown of memory optimization can lead to accelerated battery discharge. Add only really necessary applications such as instant messengers or work tools to the exceptions.
It's important to understand the difference between a standard user closing an application and a system cleaning. If you swipe the window in the Manager, the process stops. But if the application closes the MIUI system itself in the background, you lose communication with it until the next manual start, which is why setting exceptions is a must-do step after you buy a smartphone.
Basic setting of auto-launch applications
The first and most important step is auto-start permission, which is disabled by default in Xiaomi for all third-party applications for security and resource saving purposes. Without this permission, the program will not be able to start its services immediately after turning on the phone or after cleaning the memory.
To set up, you need to go to the Settings menu, and you need to find the App section and select the Permissions item, and then you need to tap the AutoRun option on the list that opens, and you'll see a complete list of installed programs with switches opposite each of them.
- 📱 Find the right app in the list, such as Telegram or WhatsApp.
- 🔘 Activate the switch to the right of the program name.
- ✅ Confirm the action in the pop-up window if the system requests permission.
Once you have auto-run, the system service will be able to start the application when you start the system, a fundamental step without which further adjustments may not make sense, but auto-runs are often not enough to run smoothly in the background of the Redmi Note 9.
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If the application you want isn’t in the autorun list, try running it manually at least once after installation.
Battery setting: No restrictions mode
The next critical step is to change the energy saving strategy for a particular application. MIUI by default puts all programs in background activity restriction mode, which means that once the screen goes out, the system begins to choke the background processes.
To change this behavior, go back to Settings and go to Battery and Performance (or simply Battery). In the upper right corner of the screen is the gear icon or three-dot menu. Click on it, select Activity Control, and here you will see a list of all programs with current status constraints.
| Mode of work | Description of behaviour | Impact on the battery |
|---|---|---|
| Saving charge | Limits background activity, may interrupt loading | Minimum |
| No restrictions. | Full access to resources in the background, priority work | Elevated. |
| Smart mode. | The system decides when to limit the process. | Average. |
You need to find your application in the list and switch it to No Limits mode. In some versions of MIUI, this item may be called "No Limits" or displayed as a choice of three options. By choosing this mode, you instruct the system to ignore the standard energy saving rules for this program.
⚠️ Note: When selecting the "No Limits" mode, the application may continue to use GPS And the Internet, even when you're sleeping on your phone.
This is the most effective setup for email clients, pedometer trackers and navigators, and it prevents connection breaks when the Redmi Note 9 screen is turned off. Without this step, navigation can be interrupted and files will not download in the background.
☑️ Checklist of battery settings
Fixing the application in the task manager
The third layer of protection for your applications is manual locking in RAM, and even with autostart and no battery restrictions, the user can accidentally clear the entire memory with a single swipe gesture, and there is a lock function to avoid this.
Open the menu of running apps by swiping from the bottom up and holding your finger (or pressing the menu button, depending on the type of navigation you want). Find the card of the application you want. Swipe the card left or right, but not all the way to the end, so that there are additional control buttons. You need a lock icon.
Press the lock icon. It should close, which signals locking. Now, even if you press the "clear" button (cross or broomstick) in Task Manager, this application will remain in memory and will not be closed. It is mechanical protection against random user actions.
- 🔒 Closed lock ensures that the application will not be unloaded when the memory is cleared.
- 🧹 Cleaning button ignores fixed applications.
- 🔄 To unlock, you need to press the lock again so that it opens.
The use of the lock is especially important for navigators (Yandex.Navigator, Google Maps) and applications for recording sound. If you forget to remove the restriction, the system will continue to keep the process in memory, which can be useful for continuous operation, but requires control.