How to Clean Memory on Xiaomi Redmi Note 9: 7 Proven Ways

Xiaomi Redmi Note 9 is still one of the most popular smartphones in the budget segment, but its 64 or 128 GB of memory have an unpleasant property to end at the most inopportune moment. and the problem is not only in the accumulated photos and videos – the MIUI system actively caches data, applications grow to giant sizes, and garbage files occupy tens of gigabytes unnoticed by the user.

In this article, you will find not template tips like “delete unnecessary photos”, but deep cleaning with the features of the Redmi Note 9, from hidden MIUI functions to manually removing system debris. We will also discuss why standard methods often do not work, and what to do if memory is filled with “invisible” files. All instructions are tested on current versions of MIUI 14 and Android 12/13 (including security updates from 2026).

1.Diagnostics: Why memory ends on Redmi Note 9

Before you clean, you need to figure out what exactly takes up space. The Redmi Note 9 has three key memory eaters:

• 📱 System cache MIUI — before 10-15 GB (including update backups, log files, and temporary application data).
• 🎮 Cache of games and social networks – Facebook, TikTok or Call of Duty Mobile can be borrowed by 1-3 GB.
• 🗑️ "Invisible files – remnants of remote applications, duplicate photos in.thumbnails, downloaded APK.

To see the full picture, go to Settings → About Phone → Memory. Here you will see a memory distribution diagram, but it often hides details. For example, the System section can take 20+ GB, although the real weight of the MIUI is about 8-10 GB. The rest is garbage.

The Redmi Note 9 with MIUI 12+ has a hidden /data/adb folder that stores update backups (up to 5GB) that can't be seen through standard conductor, but it takes up space.

2. Standard cleaning methods (and why they don't always work)

MIUI offers built-in memory-free tools, but they often only remove the tip of the iceberg.

1. Cleaning in Memory Settings → Memory → Clean: Removes application cache and temporary files, but does not touch system debris and remnants of uninstalled programs. Effect: +1-3 GB (once).
2. Deep Cleaning in Security App: More aggressive, but can remove data from some applications (e.g. saved passwords in the browser) Effect: +2-5 GB.
3. Removing duplicate photos (Gallery → Albums → Duplicates): Useful, but only works with photos taken on this phone. Doesn't see screenshots or uploaded images.

🔹 Problem: These methods do not clean:

• 📁 folder /data/app-lib remnants.
• 🔄 Cash updates. MIUI into /cache.
• 📱 Log files of the system (/data/log).

⚠️ If after a standard cleaning, the memory ends again in a day or two, the problem is in the background processes. MIUI. You need to turn off automatic optimization in Settings → Special opportunities → Optimizing memory (this will reduce performance but reduce memory consumption).

Manual cleaning: hidden folders and system debris

For deep cleaning, you will need a file manager with root rights (such as MiXplorer or Solid Explorer) or ADB. If root rights are not available, use ADB Shell (instruction below).

📌 Cleaning folders (for experienced users only!):

🔧 How to clean through ADB (rootless):

1. Install ADB Tools on your PC.
2. Connect Redmi Note 9 to USB, enable Debugging via USB (Settings → About Phone → MIUI Version → 7 times Press → Return to Additional → For Developers).
3. In the command line, type: adb shell su rm -rf /data/local/tmp/* rm -rf /cache/* exit

⚠️ Attention: Do not delete folders /data/data or /system — If you're not sure, only use the commands above.

Backup of important data |

Charge your phone at least 50% |

Install ADB Tools on PC|

Enable debugging over USB in the developer settings |

Check the free space before cleaning (for comparison)

-->

4.Cleaning the app cache: what can be removed without consequences

App cache is a temporary file that should be released automatically, but on the Redmi Note 9, MIUI often forgets to do this, and let's figure out which cache you can clean safely and which one you should not touch.

📊 Safe to remove (releases) 1-5 GB):

• 🎵 Spotify, Yandex Music - cache of songs (folder) /Android/data/com.spotify.music/cache).
• 📺 YouTube, TikTok – video cache (up to 1 GB each).
• 🗺️ Google Maps, 2GIS – cache of cards (can weigh up to 2 GB).
• 🎮 Games: PUBG Mobile, Genshin Impact – Texture Cache (up to) 3-4 GB).

❌ It is better not to touch (may break the job):

• 📱 WhatsApp, Telegram – cache of media files (if you delete, chats will remain, but you will have to download the photo / video again).
• 🏦 Banking applications (SberBank, Tinkoff) – cache may contain authorization data.
• 🔑 Google Play Services – Deleting cache will lead to sync errors.

🔹 How to Selectively Clean Cache:

1. Go to Settings → Applications → Application Management.
2. Select the application → Storage → Clear the cache.
3. For a complete cleanup, click Delete Data, but this will reset the app settings!

💡

If the app is slower after cleaning the cache, restart the phone.MIUI reassembles the cache at launch, and it can take 5-10 minutes.

5. MIUI Optimization: Disabling Unnecessary Functions

The MIUI on the Redmi Note 9, by default, includes many background processes that eat up memory.

🛠️ What can be turned off:

• 📊 Analytics MIUI (Settings → Additionally. → Confidentiality → Analytics – collects data on phone usage.
• 🔄 Auto-Update Applications (Google Play) → Settings → Auto Update – Downloads updates in the background.
• 📷 Background shooting in the camera (Camera settings) → Additionally. → Background shooting – saves photos even when the application is folded.
• 🎵 Mini-player in the curtain (Settings) → Notifications → Notification panel → Mini-player) – takes RAM and stores cache.

📉 The effect: These changes will release 1-2 GB of memory and reduce the load on the processor, especially noticeable on the Redmi Note. 9 s 3/4 GB RAM.

⚙️ Additional: Turn off animation MIUI, speed up:

adb shell settings put global window_animation_scale 0.5


adb shell settings put global transition_animation_scale 0.5




adb shell settings put global animator_duration_scale 0.5

This won’t free up memory, but it will make the interface faster.

6.Transfer data to a memory card (and why it doesn’t always work)

The Redmi Note 9 supports microSD cards up to 512GB, but MIUI limits data portability, and let's figure out what can be moved and what can't.

✅ What can I transfer:

• 📷 Photo and video (via Gallery) → highlight files → Move it to SD).
• 🎵 Music and podcasts (manually through a conductor).
• 📄 Documents (PDF, Word, Excel).

❌ What cannot be changed (limitations) MIUI):

• 📱 Applications (only if they support installation on the SD, But that's rare in 2026).
• 🎮 Game data (save, cache) remain in internal memory).
• 📁 Android folders, DCIM (system-data).

🔧 How to get around restrictions (for advanced ones):

1. Use App2SD or Link2SD (requires root).
2. Move files manually through your PC (but some apps won’t see them).
3. Set up Adoptable Storage (converts) SD-card to part of the internal memory), but it is risky - when you remove the card, the phone will stop working.

⚠️ Note: If you use Adoptable Storage, select a fast memory card (UHS-I or UHS-II). Slow Class 10 cards will slow down the system more than freed memory will help.

7.Extreme measures: reset to factory settings

If nothing works and the memory is full of invisible files, then you have Hard Reset, and on the Redmi Note 9, you can do it in two ways:

🔄 Method 1: Through settings (saves data in Mi Account):

1. Go to Settings → About the phone → Reset settings.
2. Choose to erase all data.
3. Confirm the action (you will need to enter a password from Mi Account if you are tied).

🔧 Method 2: Through Recovery (total reset):

1. Turn off the phone.
2. Press Power + Volume up until the Mi logo appears.
3. Select Wipe Data → Wipe All Data (control – volume and power buttons).

⚠️ What will be removed:

• 📱 All applications and their data.
• 📷 Photos, videos, music (if not transferred to the SD).
• 📞 Contacts, SMS, Call logs (if not synchronized with the Google/Mi Account).

🔹 How to recover after a reset:

• 🔄 Recover data from Mi Cloud or Google Drive backup.
• 📥 Reinstall apps from Google Play → Library.
• 🔧 Turn off automatic download of media in messengers (WhatsApp, Telegram).

FAQ: Frequent Memory Cleanup Questions on Redmi Note 9