Why Xiaomi is full of memory, although nothing is installed: full analysis + cleaning instructions

You open Xiaomi's settings to install a new app, but you see a red sign saying, "Memory is full." 10-15 And you haven't saved any photos or videos in a long time. Is that familiar? It's one of the most common problems that Redmi, Poco and Mi have with their smartphones. MIUI.

In this article, we're not going to talk about the trivial things like "remove unnecessary photos," but instead, we're going to look at 10 hidden reasons why memory clogs itself, from the system cache to MIUI chips you didn't know you had, and most importantly, we're going to give you step-by-step instructions on how to free 5 to 15 GB of memory without resetting to factory settings.

Spoiler: 80% of the time, it’s not your actions that are to blame, but automatic MIUI processes that don’t show up in the standard file manager, such as duplicate updates, error logs, or cache of Xiaomi smart services that can’t be turned off via the menu.

1. App cache and system cache: why they take up gigabytes

The first thing that comes to mind when you don't have enough memory is to clear the cache, but few people know that in MIUI, the cache is divided into three types, and the standard cleaning through the settings affects only one of them.

🔹 User app cache — temporary files of messengers, social networks and games. For example, Telegram can store up to 5 GB of media files, and TikTok — up to 3 GB of preloaded videos. → Annexes → Application management.

🔹 Cache of system applications - data MIUI-Services like com.miui.gallery, com.android.providers.media, or com.xiaomi.midrop, which cannot be deleted and can be cacheed to a maximum of three times. 1-2 GB.

🔹 Dalvik-cache is a hidden cache of the Android virtual machine that is created when you install / update applications. MIUI It often does not clean automatically and can eat up to 500 MB-1 GB.

• 📱 How to check: Install Files by Google from Play Market → open the section "Cleaning up" → See the volume of "App cache" and "Files" APK".
• 🧹 How to clean: Dalvik-cache requires access to recovery (see section 5). Regular cache is cleaned through Settings → Memory. → Clear the cache.
• ⚠️ Important: Do not clear the Google Play Services and Services Framework cache – this can break account sync.

MIUI Optimized Storage: Why the system downloads unnecessary files

In 2021, Xiaomi added Optimized Storage to MIUI 12.5+, which is designed to automatically delete unnecessary files, but in practice it often works the opposite way.

The feature has three hidden mechanisms that can clog up 3-8 GB of memory per month:

1. Pre-loading updates. MIUI downloads full firmware packages (1.5–3 GB) in advance, even if you do not plan to update. /data/ota_package.
2. Smart recommendation cache: com.miui.systemAdSolution collects data about your actions and downloads promotional materials (banners, videos) for the m-stor. It takes up to 1 GB.
3. Duplicate media files: When you transfer files via Mi Drop or ShareMe, temporary copies are created in /storage/emulated/0/MIUI/Share, which are not always deleted.

🔧 How to turn off:

1. Go to Settings → Memory → Storage settings.
2. Disable the options: "Automatic download updates" "Storage optimization" (if any) "Content recommendations"

ota_package

Root Explorer

Mixplorer

💡

If you have lags after you turn off Optimized Storage, restart your phone. The system will restructure the file index, and performance will recover.

Error Logs and Dumps of the System: Invisible Memory Eaters

Every time an application or MIUI system crashes, an error log (a file with the.log or.dmp extension) is created. Under normal conditions, these files take up several megabytes. But on Xiaomi, because of the kernel, they can grow to 500 MB-2 GB.

Where to look:

• 📁 /data/anr — application error tracing (ANR — Application Not Responding).
• 📁 /data/tombstones — memory dumps in case of system processes failure.
• 📁 /data/log — Logic of modules MIUI (For example, bugreport-miui*.zip).

🛠 How to remove:

1. Install FX File Explorer or Solid Explorer (root rights required).
2. Go to /data and delete the anr, tombstones, log folders.
3. If you don't have root, use it. ADB-Command: Adb shell rm -rf /data/anr/* adb shell rm -rf /data/tombstones/* adb shell rm -rf /data/log/*

⚠️ Note: Removing files from /data rootless can cause failure MIUI. If the phone stops turning on after cleaning, reset via Fastboot (fastboot erase userdata).

4. Duplicates and "garbage" of the gallery: why photos are taken in the 2-3 more

The Gallery app in MIUI has two dangerous features:

1. Automatic thumbnail creation. Each photo/video is previewed in a folder. /storage/emulated/0/DCIM/.thumbnails. Primary 1000 photo +500–800 MB.
2. Duplicates when editing. If you cropped a photo in a standard editor, the original remains in the DCIM/.edits folder, and the edited version is saved as a new file.

📊 Comparison of space occupied:

🗑 How to clean up:

• 🖼 Delete the folders: /DCIM/.thumbnails, /DCIM/.edits, /Pictures/Screenshots/.thumbnails.
• 🔍 Use Files by Google → "Cleanup" → "Duplicate files".
• 📱 Turn off auto-creating thumbnails: Gallery settings → Additionally. → Deactivate "Quick viewing".

5. Hidden Partitions and MIUI Backup Storage

There are two hidden mechanisms in MIUI that are not mentioned in the documentation:

1. Backup /data/miui: This is where you store backups of settings, themes and Mi Account data, up to 1.5GB.
2. Virtual disk /data/user_de. Used for isolated storage of application data (e.g. Mi Pay or Mi Home) 800 MB.

🔓 How to get access:

• Root-rights: Use Root Explorer and delete unnecessary files manually.
• No root: Connect your phone to your PC. Enter in ADB: adb shell su cd /data/miui ls -la Remove old backups (files with the.bak or.backup extension).

⚠️ Note: Do not delete files with the.dex or.odex extension in /data/user_de — It can break Mi Pay and other services, and it's only safe to clean the cache and tmp folders.

6 MIUI Updates: Why They Take Place Even After Installation

When updating MIUI via OTA (over the air), the system stores:

• 📦 Complete firmware package (update.zip, 1.5–3 GB /data/ota_package.
• 🗃 The old version of the firmware in /data/backup (kickback).
• 📝 Logs of installation in /cache/recovery.

🔄 How to disable automatic download of updates:

• Go to Settings → About the phone → System update.
• Click on three points → “Settings” → turn off “Automatic boot over Wi-Fi”.
• In Settings → Memory → Storage settings, disable “Auto-Soft Update”.