The flagship Xiaomi Mi 9, powered by the powerful Snapdragon 855 processor, is capable of performing well even years after its release. However, over time, the MIUI operating system has become increasingly endowed with temporary files, background processes and visuals that can significantly slow down the interface. Many users have noticed that animations are becoming less smooth and apps are opening longer than usual.
Before you think about buying a new device, you should do a deep software optimization that will bring back the sharpness of the response. In this guide, we will examine not only standard cleaning methods, but also the hidden features of the system available through the developer menu. Restoring the factory speed of the Mi 9 is possible without obtaining root rights and flashing the device.
A comprehensive approach to acceleration involves autoboot, system debris, and graphics rendering settings. Configuring these settings correctly will relieve RAM and reduce the load on the CPU. Let's look at a step-by-step algorithm for maximum performance of your gadget.
Analysis and release of system resources
The first step to speed up the Xiaomi Mi 9 is to free RAM from unnecessary processes. In the MIUI shell, many pre-installed services run in the background, consuming precious resources. Standard cleaning through the menu of recent applications is often not effective enough, since the system automatically restarts important processes for it.
It is recommended to manually analyze the list of installed applications and remove those that you do not use. Particular attention should be paid to heavy social networks and games that have the property of running their own update services. You can use built-in system tools or third-party utilities to manage the autoload of third-party programs, although new versions of Android access to this feature is limited.
An effective method is to use the built-in Security app, which allows you to force background processes to be completed in the Memory Cleanup section, and to do this routine regularly helps keep RAM free, which is critical for fast multitasking.
⚠️ Warning: Don’t install the dubious accelerator apps from Play Market that promise miraculous effects, often consuming more resources than they save, and saturating the system with ad modules.
To deepen the cache of specific applications, go to Settings → Applications → All applications. Select a resource-intensive application, such as a browser or messenger, and click “Clear Cache.” This action is safe and will not lead to loss of personal data, but will free up space on the internal drive, which also affects the overall speed of the file system.
Optimization of visual effects and animations
The visual aspect of MIUI is often the cause of perceived lag, which is the apparent slowness of the system. Smooth transitions between screens and windows take time to render. The visual experience of Xiaomi Mi 9 can be accelerated through a hidden menu of engineering settings.
To activate this mode, go to Settings → About Phone and click on the MIUI version seven times in a row. After the “You became a developer” notification appears, you will access the extended menu. In the “Developers” section, find the “Drawing” subsection.
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To instantly speed up the interface visually, zoom in on the animations by 0.5x, making the transitions between screens twice as fast without losing functionality.
You'll need three parameters: "Window animation scale," "transition animation scale," and "Animator duration scale." They're set to "1x" by default. Changing that value to 0.5x or turning off animations completely will greatly speed up the interface response. The phone will seem much faster, as the system will no longer waste time rendering intermediate frames.
- 🚀 The scale of window animation: reduces the opening and closing time of applications.
- 🔄 Transition animation scale: speeds up switching between desktops and menus.
- ⏱ The scale of the animator duration: affects the speed of the system's response to user actions.
It is not recommended to completely disable animations (meaning "No animation"), as this can disrupt visual navigation and make the interface twitchy. The optimal balance between speed and comfort of use is a value of 0.5x.
Managing Autoboot and Background Processes
Controlling which apps run with the system is a key performance factor. The Xiaomi Mi 9 has an aggressive memory management mechanism, but it doesn’t always handle heavy apps from third-party developers.
Go to the Security menu and find Permissions, and you're interested in AutoStarting. Turn off this feature for all applications that don't require instant notifications, such as email clients, news aggregators or games. Leave autoboot on for instant messengers and system services only.
☑️ Background activity check
Alternatively, you should set background activity limits for each application individually. From the Security menu, select Battery and go to the list of applications. For programs that you do not need in the background, set No Limits mode only if it is critical, otherwise you should choose Background Limitation.
There is also an Advanced Cleanup feature in the security application that allows you to delete residual files after you delete programs, and using it regularly prevents the accumulation of “digital debris” that takes up space on the disk and can slow down the system’s indexing of files.
Display settings and refresh rates
The Xiaomi Mi 9 screen features a high refresh rate Super AMOLED matrix. While this provides a smooth picture, constant high-frequency operation can load the GPU in certain scenarios. However, unlike budget models, turning off high-frequency will not give you speed gain, rather the opposite.
More importantly, pay attention to screen resolution and zoom. In the Settings menu → Screen → Resolution, make sure that native resolution is selected. Software-based resolution reduction on this device is not recommended, as the interface may become unreadable and the GPU resource savings will be minimal.
| Parameter | Recommended value | Impact on speed |
|---|---|---|
| Frequency of update | 60 Hz (standard) | Basic smoothness |
| Dark subject matter | Included. | Saving energy AMOLED |
| Frameless regime | Off. | Reducing the load on the GPU |
| Brightness | Automobile | Stability of the controller |
Using a dark topic in MIUI Not only does it save battery life. AMOLED-It also reduces the load on the display controller when rendering black, which can have a positive effect on the overall responsiveness of the interface when using the night.
⚠️ Attention: Full Screen apps makes apps run full screen, cutting off bangs. On some older apps, this can cause rendering and slowing errors.
If you notice that a particular application is slow, try turning off MIUI optimization for it. In the About Phone menu, click on the kernel version several times to open the hidden optimization menu, where you can force optimization on or off for individual applications, which sometimes solves compatibility problems.
Cleaning the storage and working with the cache
Internal memory is one of the biggest enemies of any Android smartphone’s speed. When free disk space runs out, data write and read speeds drop, leading to lags and long downloads. For the Xiaomi Mi 9, storage fills by more than 85-90% are considered a critical threshold.
Check your download folder and gallery regularly. High-resolution videos and photo series can take up gigabytes of space. Use the built-in Cleanup tool in the security app, which will find duplicate files, similar images and large video files.
How to clean the cache of the system safely?
Pay special attention to messengers like Telegram or WhatsApp, which tend to accumulate huge amounts of cache from the media files received. In the settings of the application, find the "Data Use" item and clear the cache. This action will not delete correspondence, but will free up a significant amount of memory.
If the space is running out all the time, consider transferring files to the cloud or to a computer. The eMMC/UFS file system installed in Mi 9 works most efficiently when it has free space for write operations.
Hidden functions and reset network settings
Sometimes a smartphone's slow performance is not about the processor, but about network connectivity issues. Constant attempts to reconnect to unstable Wi-Fi or search for a 4G network can strain the processor and create a sense of lag. Network resets often solve these problems.
To perform the reset, go to Settings → Connection & Sharing → Reset Wi-Fi, mobile networks, and Bluetooth. Please note that this action will remove saved passwords from Wi-Fi networks and associated Bluetooth devices, but will not affect personal files.
- 📡 Resetting settings APN: restore the correct parameters of the mobile operator access point.
- 🔒 Bluetooth reset: removes pairing errors with watches and headphones.
- 🌐 Reset DNS: Clears the domain name cache, speeding up the opening of pages in the browser.
You can also check your DNS settings. Using a fast DNS, such as from Google (8.8.8.8) or Cloudflare (1.1.1.1), can speed up the response of the browser and some applications. You can change the DNS in your Wi-Fi connection settings for a particular network or globally through your private DNS settings in the Connection and Sharing section.
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Comprehensive optimization, including memory cleaning, animation tuning and autoboot control, can return the Xiaomi Mi 9 to the feel of a new device.
In conclusion, remember to update the system. Although newer versions of MIUI are sometimes criticized for being heavy, they often contain important security and optimization patches for a specific Snapdragon 855 hardware. Check for updates in the About Phone menu and install the latest stable version.