How to speed up Xiaomi phone on MIUI 12: a step-by-step guide

Xiaomi’s MIUI 12 shell is known for its striking design and feature-richness, but over time, even powerful smartphones start to slow down. The reasons range from overloaded memory to background system activity. Fortunately, most problems are solved without drastic measures like factory resets.

In this article, we’ll take a look at the proven optimization methods that work on all MIUI 12 devices, from the budget Redmi Note 9 to the flagship Mi 11 Ultra, how to reduce CPU load, free up RAM and get rid of the lags in the interface, and what settings should never be touched to avoid making things worse.

Important: All recommendations are based on official Xiaomi documentation and tests on real devices. If your smartphone is older than 2019, some items (for example, disabling MIUI Optimization) may require superuser rights (root).

1.Cache and garbage cleanup: the first step to speeding up

System cache and temporary application files are the main memory eaters. MIUI 12 has built-in tools to clean them, but they often work inefficiently.

Go to Settings → Applications → Application Management. Here sort programs by cache size (click on three dots in the upper right corner → Sort → Cache size). Delete the cache for applications that take up more than 500 MB — this can be social networks, messengers or games.

• 🧹 Safe Cleaning: Use the built-in Security app → Cleanup. It removes garbage, but it doesn't touch important data.
• 🚫 What NOT to clean: Cache system applications (eg, com.miui.home — launcher). its removal can lead to interface failures.
• ⚡ Auto Cleanup: Include in Settings → Battery and performance → Memory Cleanup Option Automatic Cleanup When Locked.

If your smartphone is still slowing down after cleaning, check if your main memory is full. In MIUI 12, 85% is the critical threshold, which is when you exceed it, you start to "glut." Make room by transferring photos and videos to the Mi Cloud cloud or memory card.

⚠️ Note: Do not use third-party cleaners like Clean Master or CCleaner. MIUI, This causes errors in the camera or sensors.

2. Disable animation and visual effects

MIUI 12 is famous for its smooth transitions and animations, but they eat up to 15 percent of the CPU's resources, and you can turn them off through the developer's hidden settings:

1. Activate Developer Mode: Settings → About Phone → MIUI version (click 7 times in a row).
2. Back to Settings → Additionally. → For developers.
3. Find the items: Scale of window animation → No animation Size of transition animation → No animation Duration of animation → Disable

With the changes, the interface will be less lively, but the response to touch will be faster by 20-30%, especially when multitasking and opening heavy apps (like Google Chrome or Instagram).

Additionally, you can disable blur effects in Settings → Display → Animation effects. This will save up to 10% of battery life and reduce the load on the GPU.

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If after disabling animation, some applications began to open with a black screen, reboot the smartphone - this will reset the graphic cache.

3. Optimization of application background activity

Many programs continue to run in the background even when you're not using them, including messaging, social media, and MIUI system services, to limit their activity:

• 🔄 Autostart Limitation: Settings → Annexes → Application management → Autorun. disable autorun for unnecessary programs (such as games or stores).
• 📵 Background Activity: In the same application management menu, select Background Activity and set the Restrict mode for most applications.
• 🛑 Freezing System Processes: Using ADB You can turn off unnecessary services (e.g., com.miui.analytics, statistics collection) Commands: adb shell pm disable-user --user 0 com.miui.analytics adb shell pm disable-user --user 0 com.xiaomi.ab

Be careful when disabling system processes, some of which are responsible for security updates or sensors, and a full list of secure services to disable can be found on the XDA Developers forum (MIUI 12).

⚠️ Warning: Disabling com.miui.home or com.android.systemui will cause the smartphone to be completely inoperable!

4. MIUI Optimization setup: Hidden performance tumbler

MIUI 12 has a hidden MIUI Optimization feature that is enabled by default, which is responsible for smooth animations and resource allocation, but on weak devices (for example, Redmi 8A or Poco M2) can cause delays.

1. Activate the developer mode (as in the previous section).
2. Go to Settings → Additional → For developers.
3. Find MIUI Optimization and turn it off.
4. Reboot your smartphone.

The effect will not be noticeable immediately — it will take 1-2 days for the system to reallocate resources.

• Apps open faster (by 10-15%).
• Less “suspend” when switching between tasks.
• The processor heat is reduced.

However, there are downsides: some visual effects (such as smooth unfurling of notifications) may be lost. If interface artifacts appear after the shutdown, return the setting to its original state.

Make a backup copy of the data|Check the battery charge (minimum 50%)|Remember the current animation settings|Prepare for a possible reboot-->

5. Update of firmware and core: when brakes due to bugs

If your smartphone started to brake after upgrading to MIUI 12, the problem may be in unstable firmware. Xiaomi regularly releases patches that correct performance errors.

Go to Settings → About Phone → System Update. If a new version is available, install it. Pay attention to the type of update:

• 🔹 Stable version – proven firmware with minimal risk of bugs.
• 🔹 Development version (Developer) – may contain new features, but often “raw».

If the brakes are stronger after the update, try to roll back to the previous version.

1. Download the necessary firmware from the official Xiaomi website (Downloads section).
2. Rename the file to update.zip and place it in the root of the memory.
3. Press Volume Up + Power to enter Recovery.
4. Select Install update.zip.

For bootloader devices, you can install custom cores (such as FrancoKernel) optimized for performance, but this requires root rights and may be unwarranted.

6.Reset partition cache and Dalvik: Radical cleanup

If all previous methods failed, try resetting the Dalvik and Cache partition cache.This won't delete your data, but will clear temporary system files that may be causing brakes.

1. Turn off your smartphone.
2. Press Volume Up + Power to enter Recovery.
3. Choose Wipe & Reset → Wipe Cache.
4. Confirm the action and wait for the completion.
5. Reset the device.

After reset, the first turn on can take up to 5-10 minutes, which is normal. The system restores the cache of applications.

• 📈 Accelerating the launch of applications on 20-30%.
• 🔋 Reduced battery consumption (up to 15%).
• 🛠 Correction of errors with “flights” of system processes.

If that doesn’t work, the last option is factory reset. Before you do that, make sure to back up through Settings → About Phone → Backup.

⚠️ Warning: Do not confuse Wipe Cache and Wipe Data! The second option will delete ALL your data, including photos and contacts.

7. Alternative launchers and lightweight firmware

If MIUI 12 is not satisfied with the main problem, consider replacing it:

• 🏠 Third-party launchers: Install Nova Launcher or Lawnchair.They consume less resources and allow you to disable unnecessary widgets MIUI.
• 📱 Custom firmware: For power users, LineageOS or Pixel Experience, which lacks a heavy interface MIUI, but require unlocking the loader.
• ⚡ Lightweight versions MIUI: There are modified firmware on the forums MIUI 12 Lite, where unnecessary services are removed (e.g. Mi Video or Mi Music).

Before installing custom firmware, check its compatibility with your model on the XDA Developers website. Incompatible software can lead to a "brick" (complete inoperability) of the device.

For devices with 4GB of RAM and less, try MIUI 12.5 Enhanced, an optimized version of the shell released specifically for weak smartphones. It is available for Redmi Note 8/9, Poco X3 and others.

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Installing custom firmware voids the warranty and can lead to problems with air updates (OTAs).

FAQ: Frequent questions about Xiaomi’s acceleration MIUI 12