Owners of Xiaomi, Redmi and POCO smartphones sooner or later face inexorable filling of internal memory. The system begins to warn of a critical level of free space, and the speed of the device drops markedly. In an attempt to free up space, users often find huge folders with mysterious names in the storage or see that the Data partition takes up gigabytes, although specific files cannot be found.
Many people immediately think of the hidden system directories that Android has traditionally hidden from the eyes of the average user. However, in the MIUI ecosystem and the new HyperOS, file management is more complicated than in pure Android. It is important to understand what you are going to delete so as not to turn the phone into a brick or lose correspondence and logins.
In this article, we will discuss in detail what data files on Xiaomi smartphones are, how cache differs from user data and what actions are really safe for the system. We will look at both standard cleaning methods and advanced ways to work with the file system through a computer.
The Nature of System Files and Data Folders
The Android operating system on which Xiaomi shells are based is the Linux file system. The /data root partition is the most important storage where all user information is recorded. This includes installed applications, their settings, messenger databases, downloaded files and cache. For the average user, this partition is hidden, but its volume is visible in the storage statistics.
When you see a data or other partition taking up the lion's share of memory, it means that apps have accumulated a huge amount of temporary information. For example, messengers like Telegram or WhatsApp can store media files for years, which are formally part of the app's data, rather than individual photos in the gallery, the system considers these gigabytes to be busy payloads, although often it is just an old cache.
Special attention should be paid to the folder structure on modern devices with the shell HyperOS. Google has changed the rules for accessing the file system in Android 11 and above, limiting access to the root directory Android/data. This is done for security reasons, so that apps can't steal data from each other, but it's created confusion: users see folders, but they can't go inside without special permissions or a PC connection.
⚠️ Warning: Never try to delete files directly from the root system folder /data through root-right file managers, if you don't know the exact purpose of each file.Deleting system libraries (.so files) or settings databases (.db) will result in unstable operation or cyclical reboot.
Difference between Cache and Application Data
It's critical to clean up memory properly, and it's critical to distinguish between cache and application data. Cache is a temporary file that speeds up programs. This includes thumbnails of images, saved web pages, a video streaming buffer. Cache deletion is safe: the app will just recreate those files when they're needed, perhaps a little longer on the first time it's downloaded.
This section includes logins, passwords, interface settings, game progress, downloaded maps for navigation and correspondence history. If you click Clear Data (or Reset) in the app settings, the program will return to the "as after installation" state, all your accounts will be logged out and local settings reset.
Consider the example of a Yandex Navigator or Google Maps navigator. Cache here is the images of map tiles you viewed yesterday. Data is downloaded offline maps of entire regions, a list of favorite places and search history. Cache clearing will free up a couple hundred megabytes, and data clearing will force you to re-download maps, spending mobile traffic.
- 📂 Cache – temporary files for acceleration, deleted without consequences for functionality.
- 🔐 Data – user settings and logins, deletion resets the application.
- 💾 Warehouse (OBB) — heavy game files that require re-downloading.
- 🗑️ Residual files – “tails” of remote applications, safe to delete.
The MIUI shell has a built-in cleanup utility that tries to automatically balance security with freeing up space, but it often works superficially, fearing to affect important system processes. For deep cleaning, it is better to use manual control through the settings of a particular application.
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Before clearing the messenger data, be sure to back up the correspondence to the cloud (Google Drive or iCloud), otherwise the message history will be lost irretrievably.
Android folder analysis: data and obb
The heaviest and most questionable part of the file system is the Internal Memory → Android path, where two key subfolders are located: data and obb. Understanding their structure will help you make room safely without removing the extra, the data folder stores application work files, and the obb contains additional resources, most often for games.
High-graphics games like PUBG Mobile, Genshin Impact or Call of Duty, upload the main resource pack to obb. It can weigh between 2 and 10 gigabytes. If you delete the contents of the obb folder, the game will start, but it will require you to re-download all the resources, because without them it will not be able to draw game worlds. It will not break the phone, but it will waste your time and traffic.
The data folder inside the Android directory stores more important configuration files. It can contain messenger databases, social network cache, and temporary browser files. Modern versions of Android prohibit third-party file managers from viewing this folder. You will see folders with names like com.telegram.messenger, but when you try to log in, the system will give an access error.
Why the folder Android/data idle?
There's a myth that the Android/data folder stores viruses or unnecessary system debris that you need to clean regularly. It's not. The size of this folder is directly dependent on user activity. If you actively use social networks and play games, the folder will grow. You can't artificially limit its growth without losing the functionality of the applications.
Safe Memory Cleanup Techniques on Xiaomi
Before you get into the system wilds, you should use the standard and secure methods that Xiaomi itself offers. They are designed with the characteristics of the file system and do not violate the integrity of the OS. The first step is to use the built-in Security application, which is preinstalled on all devices of the brand.
Launch Security and select Cleanup. The system will analyze the storage and suggest removing the cache, residual files and large files. Beware: Big Files may contain important documents or original photos that you forgot to transfer to your computer. Always check the list before confirming deletion.
☑️ Safe cleaning algorithm
The second effective method is manually cleaning through settings. Go to Settings → Apps → All apps. Sort the list by size of space occupied. Go to the heaviest apps (usually browsers, social networks, instant messengers) and click on Storage. Here you will see a clear separation: how much the application weighs, how much data and how much cache. The Clear Cache button is absolutely safe here.
The third method is to use the Memory Cleanup feature in recent apps, and by clicking on the broom icon in the running task menu, you release RAM, but not internal storage. However, new versions of HyperOS may have an extended cleaning menu that affects some temporary storage files if you press the broom long enough.
| Cleaning method | What's removed | Security | Efficiency |
|---|---|---|---|
| Standard cleaning | Cash, APK remnants, sketches | Tall. | Low/Mediocre |
| Data resetting of the annex | Logins, settings, cache, databases | Medium (needs backup) | Tall. |
| Delete the.thumbnails folder | Gallery miniatures | Tall. | Medium (temporary) |
| Third-party cliners | Cash, temporary files. | Average (much advertising) | Low. |
And I'm also talking about the.thumbnails folder, which is inside the hidden DCIM directory, which stores thumbnails of your photos for quick display in the gallery. Over time, this file can grow to a few gigabytes. It can be safely deleted, but the system will recreate it when you open the gallery. To prevent sprawl, some users create a stub file with the same name, but that requires root rights.
Risks of deleting system files
The desire to free every megabyte can lead to fatal errors. On the Internet, you can find tips for deleting files with names that contain a system, vendor, miui or framework. This is absolutely not allowed. These files are responsible for the operation of the interface, communication with hardware, camera modules and basic functions of the phone.
For example, deleting folders associated with Google services (com.google.android.gsf) or Xiaomi services (com.miui.cloudservice) will cause contact synchronization, device search, push notifications and the Play Market store to stop working.
⚠️ Note: If after deleting any file, the phone begins to behave inadequately (sound disappears, Wi-Fi does not work, system applications fly out), immediately perform a full reset to factory settings. Continuing to use a device with a corrupted file system is dangerous for your data.
Of particular danger are the so-called “optimizers” with dubious reputations, which promise to speed up the phone by 5 times. Often they do not just clean the cache, but aggressively unload processes and delete files that the system considers important for fast work. In the long run, such actions only harm the Xiaomi smartphone, forcing the processor to constantly recreate remote structures.
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The safest way to free up space is to transfer photos and videos to your computer or the cloud, as well as regularly clean the messenger cache through their built-in settings.
Advanced Cleaning Through ADB and PC
For power users who don’t have enough regular methods, there is a way to clean through a computer using USB debugging (ADB), which allows you to access files that are hidden from normal viewing and remove really unnecessary ones, such as old system logs or update cache.
To start, activate Developer Mode. Go to Settings → About Phone and quickly click on MIUI or HyperOS 7 times. Then, in the advanced settings, turn on “Debugging USB.” Connect your phone to your PC, install ADB drivers, and start the command line.
adb shell pm trim-caches 999999999This command forcibly caches all applications, freeing up space, and you can use the command to delete temporary files:
adb shell rm -rf /data/local/tmp/*Using ADB requires caution. One wrong command can delete the wrong thing, but it's a powerful tool in the hands of a specialist. If you're not sure what you're doing, you'd better just plug your phone into your computer in File Transfer mode and manually sort the Download, DCIM, and Bluetooth folders.
Prevention of memory overflow
The best way to combat space shortages is to prevent: set up automatic uploads of photos and videos to cloud services like Google Photos, Yandex.Disk or Xiaomi Cloud. Enable the “Free Space” feature, which automatically deletes files already stored in the cloud from the device.
Check your messaging settings regularly. Telegram allows you to set a media storage limit (e.g., 3 days or 1 week), after which files will be deleted from your phone’s memory, remaining available in the chat cloud. WhatsApp can turn off auto-save to the gallery so that files do not duplicate.
- 🔄 Set up autodelete in Telegram in the section "Data and memory».
- ☁️ Use cloud storage to archive old photos.
- 📵 Turn off WhatsApp status autosave in the gallery.
- 🧹 Once a month, you will review the downloaded files in the Download folder.
By following these simple rules, you can keep your Xiaomi smartphone in top condition without having to risk the integrity of system files.Memory is a resource that requires management, but don't turn phone maintenance into a constant fight against gigabytes.