How to Clean Memory on Xiaomi Mi 9: From Cache to Hidden Files

Why Xiaomi Mi 9 is slowing down and how it relates to memory

The Xiaomi Mi 9, released in 2019, is still popular with users thanks to its powerful Snapdragon 855 processor and 6GB of RAM. However, even these features do not save from slowdowns if internal storage is filled with unnecessary files and the application cache is bloated to giant sizes. Typical symptoms: applications open for a long time, the system hangs when switching between tasks, and the settings are lit up with a warning of memory shortage.

The main memory eaters on the Mi 9:

• 📁 App cache (especially social networks, instant messengers and games)
• 🎥 Media files from chats (Telegram, WhatsApp, Viber)
• 🗑️ Residual files after deleting programs
• 🔄 Photo duplicates (created when editing or synchronizing with the cloud)
• 📦 Updates MIUI, which are not automatically removed

This article features unique cleaning techniques that work specifically on the Mi 9 with MIUI 12-14 firmware (including hidden features and commands for power users). Some methods require root rights, but most are available without them.

Method 1: Integrated MIUI cleaning (quickly and without risk)

The safest method is to use the built-in Security → Cleanup tool, which removes temporary files, cache and residual debris without compromising data. The Mi 9 is more efficient than newer models, thanks to optimization for Android 9-10.

Step-by-step:

1. Open Settings → Applications → Security.
2. Slip on the Cleanup.
3. Wait for the analysis (it will take 10-30 seconds).
4. Click Clean next to categories: 🧹 Garbage files (remains after uninstallation) 🗃️ Application cache (can be selectively cleared) 📎 Large files (video, APK, archive)

Clean up

⚠️ Note: Do not clear the cache for Google Play Services, MIUI System and Android System WebView – This can cause disruptions to Google services and system applications.

Method 2: Manually cleansing the cache for individual applications

If your smartphone is slowing down because of a particular app (like Instagram or TikTok), it’s better to clear the cache just for it, not for the whole system.

How to do this:

• 🔧 Go to Settings. → Annexes → Application management.
• 🔍 In the search bar, enter the name of the problem application.
• 📊 Slip it on the vault. → Clear the cache.
• 🚫 If you need to reset the app settings, click Clear Data (this will delete accounts and saves!).

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Once you clean the Google Play Market cache, manually update it through Settings → Apps → Google Play Market → Update. This will prevent errors when installing new programs.

Method 3: Remove duplicate photos and unnecessary media files

One of the heaviest storage on the Xiaomi Mi 9 is the DCIM folder, which accumulates over time:

• 📸 Duplicate photos (created when editing in Google Photos or Gallery) MIUI)
• 🎬 Videos from messengers (automatically saved in the WhatsApp/Media or Telegram/Telegram Video)
• 📁 Screenshots (daddy) Pictures/Screenshots)
• 🔍 Cache thumbnails (folder.thumbnails – can be removed completely)

To search for duplicates, use the applications:

• 🔹 Files by Google (Cleanup tab) → Duplicate files)
• 🔹 CCleaner (Section Optimization) → Duplicate)
• 🔹 Gallery Doctor (specialized in photography)

⚠️ Note: Before mass deletion, check the folder MIUI/Extra — There may be screenshots with important information (codes, checks, tickets) that are not duplicated in the main gallery.

Method 4: Clean Memory through Recovery Mode (for experienced)

If the smartphone is slowing down and does not respond to standard methods, cleaning the cache through Recovery mode will help. This method does not delete user data, but resets the system cache, which often solves problems with hanging.

Instructions:

1. Turn off the Xiaomi Mi 9.
2. Press the Power button + Volume up until the Mi logo appears.
3. In the Recovery menu, select Wipe & Reset → Wipe Cache (control – volume buttons, confirmation – power button).
4. After cleaning, restart through Reboot → Reboot to System.

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Cache cleaning in Recovery DOES NOT delete photos, contacts, or apps, but it can reset some system settings (such as region or language).

⚠️ Warning: Do not confuse Wipe Cache with Wipe Data! The second option (hard reset) will completely reset the smartphone to factory settings.

Method 5: Optimization of RAM (RAM)

On the Xiaomi Mi 9 with 6GB of RAM, performance issues are often not due to memory shortages but to RAM leaks due to poorly optimized applications. MIUI has a built-in RAM management tool:

How to enable optimization:

• 🛠️ Go to Settings. → The phone.
• 🔧 Tap 5 times on the version MIUI, activate the developer mode.
• 🔄 Back to Settings → Additionally. → For developers.
• 📈 Find the Process Limitation option and select the Standard Limitation (this will prevent overloading). RAM background).

Additional tips for RAM release:

• 🚫 Turn off window animation in the developer settings (set the animation scale on the 0.5x or off.).
• 🔄 Use lightweight versions of apps (e.g. Facebook Lite, Messenger Lite).
• 📵 Disable Auto-Run Unnecessary Programs Through Security → Auto-start.

Method 6: Transfer applications to memory card (if supported)

Xiaomi Mi 9 doesn’t have a microSD slot, but if you’re using it, it’s not a good idea. OTG-You can use a drive or you can plug a flash drive into an adapter, and you can transfer some of the data manually:

• 🎵 Music and podcasts
• 📚 Books and documents
• 🎮 Some games (such as Minecraft or Stardew Valley) allow you to choose the installation path)

How to transfer files:

1. Connect. OTG-smartphone-storage.
2. Open Mi File Manager and find folders with heavy files (such as Music or Download).
3. Select files, click Move and select OTG-target-driven.
4. For applications, use Settings → Apps → [Title] → Storage → Change (not available for all programs).

Method 7: Reset to factory settings (last resort)

If all previous methods failed, then you have hard reset, which is a complete reset of your smartphone, which will remove everything, including apps, photos and settings, so only use it as a last resort.

How to drop Mi 9:

• 🔄 First, make a backup through Settings. → Additionally. → Backup and reset → Local backup.
• 📱 Go to Settings. → The phone. → Resetting settings.
• 🔐 Choose to erase all data and confirm the action.
• 🔄 After restarting, set up your smartphone as new.

⚠️ Note: On the Mi 9 with the bootloader unlocked, the reset may result in the device being locked (requires re-unlocking via the Mi Unlock Tool).

FAQ: Frequent questions about memory cleaning on Xiaomi Mi 9