Cache Clearing on Xiaomi Redmi Note 9S: A Complete Guide to Speeding Up Your Phone

Xiaomi Redmi Note 9S is a popular smartphone with a powerful Snapdragon 720G processor and 4/6 GB of RAM, but even it eventually begins to “slow down.” The main reason is clogged: temporary application files, residual update data and fragmented system processes. Cache cleaning helps to return performance without radical measures like resetting to factory settings.

In this article, you’ll find 5 proven ways to clean up cache on the Redmi Note 9S, including hidden system tools that not everyone knows: how to remove the cache of individual applications, clean Dalvik-cache (critical for Android performance), and even automate the process with built-in MIUI features. And a unique method for models with an unlocked bootloader that gives access to deep root-cleaning without rights.

Important: not all types of cache should be deleted without thinking, for example, cleaning the cache of Google Play Services can cause malfunctions in Google services, and deleting the cache of system applications sometimes requires rebooting, we will explain in detail which files can be safely cleaned and which should be careful.

1.What is cache and why should it be cleaned on Redmi Note 9S

Cache is a temporary file that creates apps and a system to speed up its work, for example, when you first open Instagram, it uploads photos and videos to cache so that it can show them instantly the next time you run them, and browsers, games, and even system services do the same.

The problem is that over time, the cache:

• 📉 It takes up gigabytes of memory – on the Redmi Note 9S s 64/128 GB is particularly noticeable.
• 🐢 Slows down the system – fragmented cache files cause the processor to spend resources on processing them.
• 🔄 Failures – corrupted cache files can lead to crashes of applications.
• 📱 Accelerates memory wear – frequent cache overwriting increases the number of write cycles (relevant for eMMC memory in budget smartphones).

On the Redmi Note 9S, the cache is divided into three types:

1. App cache – temporary files of each installed application (for example, WhatsApp, Chrome).
2. System cache is a file that MIUI creates to speed up the interface and services.
3. Dalvik-cache – Optimized versions of applications for the Android virtual machine (removed only through Recovery or ADB).

⚠️ Warning: Cleaning Dalvik-cache without rebooting can cause a phone to cycle back (bootloop).Always restart the device after manipulating this type of cache.

2. Method 1: Clearing the cache of individual applications through settings

The safest method is to remove the cache for specific applications, which will not affect their data (saved games, chats in messengers), but will free up space and can eliminate small bugs.

Instructions:

1. Open Settings → Applications → Application Management.
2. Select an app (such as Facebook or YouTube).
3. Press Warehouse. → Clear the cache.
4. For a complete cleanup (including app data), select Clear all data, but remember: this will delete accounts, settings, and game progress.

Which apps should be cleaned first:

• 📱 Social networks (Facebook, Instagram, TikTok) – can take up to 1-2 GB of cache.
• 🌍 Browsers (Chrome, MIUI Browser – Store copies of visited pages.
• 🎮 Games (PUBG Mobile, Call of Duty – cache textures and levels.
• 📷 Gallery and camera – photo/video miniatures can be duplicated.

Facebook|Instagram|Chrome|YouTube|MIUI Browser|Gallery|Google Play Services-->

If the application after cleaning the cache began to work worse (for example, it loads data for a long time), just restart it - the system will create a new cache.

3. Method 2: Clean the entire cache through the storage menu

MIUI offers a built-in tool to mass-clean the cache of all applications at once.It's faster than cleaning each application individually, but less flexible - you can't choose what to delete.

How to do this:

1. Go to Settings. → Warehouse.
2. In the Device Memory section, click Clean (or Free in newer versions of MIUI).
3. Select the Cache Data and confirm the cleanup.

What's removed:

• ✅ Cache of all user applications (except system applications).
• ❌ Does not affect the data of applications (saves, accounts).
• ❌ Does not clean Dalvik-cache or system cache.

⚠️ Attention: If after mass cleaning of cache the smartphone began to warm up more or discharge faster, it is normal - the system restores cache for frequently used applications. After 1-2 days, the work stabilizes.

4. Method 3: Clean Dalvik-cache and system cache via Recovery

This is a method that works for power users. Dalvik-cache is an optimized application file for the Android virtual machine. Cleaning it up can speed up the system, but it requires a reboot. On the Redmi Note 9S, you need to go to Recovery Mode.

Instructions:

1. Turn off the phone.
2. Press the Power button + Volume up until the Mi logo appears.
3. In the Recovery menu, select the language (if required).
4. Go to Wipe & Reset → Wipe Cache.
5. Confirm the cleanup and wait until it is completed.
6. Restart the device (Reboot) → Reboot to System).

What exactly is being cleaned:

• 🗃️ Dalvik-cache – Recreated the next time you run your apps.
• 🧹 System cache - temporary files MIUI.
• ⚠️ Does not affect user data (photos, messages).

This method is especially useful if:

• 📱 The smartphone is slowing down after the update MIUI.
• 🔄 Applications are crashed with the error "Application is stopped".
• 🔋 Battery discharges faster than usual due to background processes.

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If you often clean Dalvik-cache, install the Quick Reboot app from Google Play – it lets you reboot to Recovery straight from the Android interface, without manually clamping buttons.

5. Method 4: Automatically clean the cache with Security App

MIUI has a built-in Security app that can automatically clear the cache and optimize the system, which is suitable for those who do not want to manually go into settings.

How to set up automatic cleaning:

1. Open the Security app (the shield icon).
2. Go to the Cleaner section.
3. Press Deep Clean (Deep Clean)
4. Select the app cache and start the process.
5. For automatic cleaning, enable the Auto Clean option in the application settings.

Advantages of this method:

• ⏱️ Fast – cleaning takes less than a minute.
• 🤖 Automatically – you can set a schedule (for example, once a week).
• 🛡️ Security – Security does not delete critical system files.

Disadvantages:

• 🚫 Does not clean Dalvik-cache.
• 📊 May miss the cache of some system applications.

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Xiaomi’s Security app is the safest way to clean up cache for beginners, as it doesn’t affect system files and offers error recovery.

6. Method 5: Clearing the cache through ADB (for advanced users)

If you're familiar with ADB (Android Debug Bridge), you can clear the cache more flexibly, like removing the cache of all applications at once or specific system files, which requires a computer and enabled USB debugging.

Instructions:

1. Enable Developer Mode on Redmi Note 9S:

What teams do:

• pm trim-caches 1000000000 – clears the cache of all applications, limiting its size to 1 GB (you can specify another value).
• pm clear [package] – completely resets the data and cache of the specified application.

⚠️ Note: pm clear command deletes all application data, not just cache! To clean only cache use: adb shell pm clear --cache-only [package] But not all apps support this flag.

This method is useful if:

• 🔧 You need to clear the cache of system applications that do not appear in standard settings.
• 📊 Mass cleaning is required without manual selection of each application.
• 🔍 You need to remove the cache of a specific package (for example, for debugging).

7.How often do you need to clear the cache on the Redmi Note 9S

The cleaning frequency depends on how you use your smartphone:

Signs that it is time to clear the cache:

• 📱 Applications are long to open or fly out.
• 🔋 Battery discharges in 4-5 hours without active use.
• 📲 B Settings → Storage is occupied by more than 5 GB of "Other files".
• 🔄 The phone overheats for simple tasks (for example, in messengers).

Do not clean the cache too often – this can lead to:

• ⚠️ Increased traffic – applications will download data again.
• 🐢 Slowdown – the system will constantly recreate the cache.
• 🔋 Fast discharge – frequent overwriting of files increases the load on the processor.

FAQ: Frequent questions about cleaning up the cache on the Redmi Note 9S