Owners of the popular budget smartphone often face a slowdown after months of active use. The main reason for the performance drop in the Xiaomi Redmi 9 is the accumulation of temporary files that take up precious space in internal memory. Android operating system and the MIUI shell create copies of data to quickly load applications, but over time these files become useless load.
Regularly cleaning the cache allows not only freeing up gigabytes of free space, but also significantly speeding up the response of the interface. Many users mistakenly believe that for deep cleaning you need to download third-party utilities that consume resources themselves. In fact, embedded MIUI tools do the job much more efficiently and safer for the system.
In this article, we will discuss all available methods for deleting temporary data, from standard cleaning through settings to using the engineering menu. You will learn to distinguish the system cache from the application data, which will help to avoid the accidental deletion of important information such as logins and passwords. The right approach to memory maintenance will extend the life of your Redmi 9 and keep it fast at a high level.
Why you need to clean the cache on Android
Cache is a buffer memory that stores temporary files to speed up programs. When you launch Instagram or YouTube for the first time, the system downloads images and data, storing them locally. When you re-enter, the application reads information from the phone's memory, not from the Internet, which makes it faster. However, over time, these files can reach several gigabytes, occupying up to 30% of available memory.
The problem of accumulation of junk files is especially relevant for models with a small amount of built-in storage, like Xiaomi Redmi 9 in the base version of 32 or 64 GB. Overflowing cache leads to the fact that the system does not have enough resources to write new temporary data, which causes "freeze" and spontaneous closure of applications. In addition, old cache files can conflict with updated versions of programs, causing errors in operation.
It is important to understand the difference between cache and application data. Deleting cache is safe and does not affect your personal settings, accounts or game progress. At the same time, cleaning the data resets the application to a “post-installing” state, requiring re-authorization.
There are several types of cache: system, application cache and browser cache. Each requires a customized approach to cleaning. System cache often contains remnants of deleted programs or temporary MIUI update files. Browser cache stores copies of visited pages, which is useful for offline browsing, but meaningless unless you plan to visit a site again without the Internet.
Use of the built-in Security application
The easiest and most reliable way to clean the cache on Xiaomi Redmi 9 is to use the regular utility from developers. MIUI shell has a deeply integrated optimization tool that scans the system for garbage files. To get started, look for an icon on your desktop called Security (green shield) and run it.
Once you open the app, click on the Cleanup button in the top left corner or select the appropriate widget on the home screen. The system will automatically analyze the memory and show the amount of debris detected. Press Clean to delete temporary files. This method is safe, since the algorithm does not affect important system files or user personal data.
☑️ Checking before cleaning
For a deeper cleaning inside the Security app, go to Clean up and scroll down the screen, and you'll see categories of files that you can delete: large files, unused apps, duplicate photos, and app cache. Selective cleaning allows you to control what's being removed from the device, for example, you can safely remove the video service cache, which often takes up the most space.
It is recommended to perform this procedure at least once a week to maintain optimal performance. If you are actively using instant messengers, the cache volume can grow very quickly. The built-in MIUI tool can recognize and safely clean the cache of popular applications like Telegram and WhatsApp without deleting correspondence.
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Set up automatic cleaning in the Security app so that the phone will remove the garbage itself when a certain memory filling threshold is reached.
Manually cleaning the cache of specific applications
Sometimes the built-in scanner doesn’t remove all the debris, especially if it’s heavy social media, and in such cases, you need to manually clean through the system settings, which allows you to monitor the amount of space occupied by each particular application on your Redmi 9 in detail.
To access application memory management, follow the following steps:
- 📱 Open the Settings menu and select the Application section.
- 🔍 Click All Apps and find the program you want (such as YouTube or TikTok) in the list).
- 💾 Select the option Memory or Storage in the menu that opens.
- 🗑️ Click the Clear Cache button at the bottom of the screen.
This is especially useful for applications you use daily, such as video services that can accumulate gigabytes of cached videos you've already watched, and manually cleaning them regularly frees up a significant amount of memory. Please note that the Clean Everything button will also delete your login data, so only use it if you plan to log in again.
Some versions of MIUI have the Advanced Cleanup feature, which shows a detailed breakdown by file type within the application, which allows you to see how much space is occupied by images, videos or just temporary files. If the application is not working correctly, a complete cleanup of data (not only cache) often solves the problem with hangings.
What to do if the cleaning button is inactive?
Cleaning the cache through the Recovery menu
For advanced users who want to perform deep cleaning of system partitions, there is a Recovery mode. This method removes temporary system update files and deep system cache, which is not available through normal settings.
To enter recovery mode on Xiaomi Redmi 9, you need to turn off the phone completely. Then press the Volume Up button and the Power button at the same time. Hold them until the MI logo appears, then release the power button, continue to keep the volume. In a few seconds, the MIUI Recovery menu with the English interface will open.
Navigation in this menu is done with volume buttons (up-down), and the choice is confirmed by the power button. You need to find the Wipe Data item. Within this menu, select the Wipe Cache option. The system will request confirmation of action — agree. After the process, select Reboot to restart the phone.
⚠️ Note: In the Recovery menu, it is crucial not to confuse the Wipe Cache option with Wipe All Data.The second option will completely reset your phone to factory settings, removing all your photos, contacts and installed apps without the ability to restore it.
This method is recommended if the phone is unstable after a major firmware update or if the free space in the system "disappeared" for no apparent reason. The system cache in the Recovery section can take up to 1-2 GB, which is a significant amount for a budget device.
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Recovery mode allows you to remove system debris that is not available for conventional software, which is especially useful after the MIUI update.
Comparison of Memory Cleaning Methods
The choice of cleaning method depends on your goals and the current state of your smartphone, and to help you decide which strategy is right for your Redmi 9, we have prepared a comparison table of the main methods.
| Cleaning method | Security | Efficiency | Risk of data loss |
|---|---|---|---|
| Security Annex | Tall. | Medium | Absent. |
| Manual cleaning of applications | Tall. | High (for selected apps) | Minimum (logins only) |
| Recovery Menu (Wipe Cache) | Medium (requires caution) | Maximum | Not available (with the right choice) |
| Third-party cliners | Low (advertising, access) | Low. | Medium. |
As you can see from the table, embedded MIUI tools are the most balanced solution. Third-party apps often create more problems than they solve by imposing ads and collecting user data. Using the Recovery menu gives the best result, but requires technical literacy.
For daily use, a combination of automatic widget cleaning and manual cleaning of heavy messengers once a month is enough. Deep cleaning through Recovery is rarely required, usually no more than once every six months or after system updates.
Frequent mistakes and helpful tips
Many users make the typical mistakes of trying to speed up their Xiaomi Redmi 9. One of the most common is installing a lot of antivirus and accelerator apps, which are constantly hanging in RAM, consuming processor and battery resources that they are supposed to save.
Another mistake is trying to clear the cache of all applications immediately through the developer settings or ADB-This can lead to the system having to reload all the resources the next time it runs an application, which puts an extra strain on the processor and the network. The cache is designed to speed up work, so removing it completely and permanently is counterproductive.
- 🚀 Do not delete the cache of cards (Google Maps, Yandex.Maps), if you plan a trip without the Internet - you will lose the ability to view offline maps.
- 📸 Check the folder regularly DCIM/.thumbnails, where the miniatures of the photo gallery are stored; cleaning it can free up hundreds of megabytes.
- 🔄 After cleaning up the heavy game cache, it may be necessary to re-load additional resources on the first run.
Also worth mentioning is the memory extension feature, which is available on some versions of MIUI for Redmi 9. It uses some of the internal memory as RAM. If you actively clean the cache, make sure that this feature does not conflict with the recording processes, although in practice they are independent.
⚠️ Warning: If after cleaning the cache, the application stopped starting or crashes immediately after opening, try to clear its data completely or reinstall the program.