How to clear cache on Xiaomi Redmi Note 9 Pro: a complete guide to speed up your smartphone

Why should Redmi Note 9 Pro cache be cleaned regularly?

Cache is a temporary file that creates applications and a system to speed up work. On the Xiaomi Redmi Note 9 Pro with its 6/8 GB of RAM and 64/128 GB of ROM, the cache can take up to 5-15 GB of memory if it is not cleaned for years. The problem is that over time these files fragment, become obsolete and begin to slow down the smartphone instead of helping.

Did you notice that Redmi Note 9 Pro has become slower to open apps, bask for no reason, or give out an error "Not enough memory" when installing updates? 80% of the time it is the cache that is to blame. Cleaning it will not delete your photos, contacts or messages, but will return the phone to speed, as after purchase. And if you actively use social networks (TickTock, Instagram), instant messengers (Telegram, Watsup) or games (PUBG, Genshin Impact), the cache of these applications can eat up to 3-4 GB of memory monthly.

In this article, we have 5 proven ways to clean up the cache on the Redmi Note 9 Pro, including hidden MIUI settings that not everyone knows, and we will also look at how to automate the process so that you don’t do it manually every month.

Method 1: Clearing the cache of individual applications through settings

The most targeted method is to remove the cache of only the programs that occupy the most space, which is safe and does not affect account data or save in games.

How to do this:

1. Open Settings → Applications → Application Management.
2. Slip on the three dots in the upper right corner and select "Sort by size."
3. On the top of the list, you'll find the most voracious programs. Click on the app you want (like YouTube or Facebook).
4. Select Clear Cache (not to be confused with Clear Data – it will delete all app settings!).

The typical "culprits" of the big cache on the Redmi Note 9 Pro:

• 📱 Social media: TikTok (up to) 2 GB), Instagram (1-1.5 GB), Facebook (800 MB–1.2 GB).
• 🎮 Games: Genshin Impact (up to 5GB), PUBG Mobile (1.5–2 GB), Call of Duty (1–1.5 GB).
• 🌍 Browsers: Chrome (500 MB-1 GB), Mi Browser (300-600 MB).
• 📺 Streaming services: YouTube (up to 1 GB), Netflix (400-800 MB).

Close the application through the multitasking menu

Connect your phone to charge (if your battery level is below 30%)

Check if there is any important unsaved data (for example, drafts in messengers)

Remember the username/password from the application (sometimes you need to re-enter)-->

⚠️ Warning: After cleaning the cache, some applications (such as Google Maps or Yandex.Maps) will take longer to load on the first run — this is normal.

Method 2: Automatically clean the cache through "Security"

MIUI has a built-in optimization tool called the Security app, which not only cleans the cache, but also closes the background processes, saving battery life.

Step-by-step:

1. Open the Security app (if it is not on the desktop, search by phone).
2. Click on "Optimization" (lightning icon).
3. Wait for the scan to be completed (usually 10–30 seconds).
4. Tap "Clean" next to the item "Junk files" (here is exactly what the cache is hiding).
5. Confirm the action by clicking "Clear" in the pop-up window.

Advantages of this method:

• 🔄 Clears the cache of all applications at once, not one at a time.
• 📉 It also removes unnecessary APK-files left over after installing programs.
• 🔋 Closes background processes that consume the battery.

⚠️ Warning: If the phone is even slower after being cleaned through Security, it may not be the cache that is the problem, but the memory fragmentation).

Method 3: Clearing the browser cache (Chrome, Mi Browser, Firefox)

Browsers are one of the main cache drives. On the Redmi Note 9 Pro, they can take up to 1-2 GB of storage, especially if you often watch videos online or download files.

Instructions for popular browsers:

💡 Useful tip: If you use your browser frequently, turn on the Traffic Saving option (available in Chrome and Opera), which compresses data and reduces cache volume by 30-50%.

💡

After clearing the browser cache, some sites can open longer on the first visit, which is normal – they re-upload temporary files.

Method 4: Cleaning the system cache with Recovery Mode

If the phone is slowing down a lot and the previous methods didn't help, the system cache (aka Dalvik-cache) may be clogged. It can't be deleted through the usual settings - you need to go to Recovery Mode.

⚠️ Note: This method does not delete your data, but if you do something wrong (for example, choose "Wipe Data" instead of "Wipe Cache"), you can lose all files!

Step-by-step:

1. Turn off the Redmi Note 9 Pro.
2. Press the Volume Up + Power buttons at the same time and hold for 10-15 seconds until the Mi logo appears.
3. Release the buttons. You will be taken to the Recovery Mode menu (English or Chinese).
4. Use volume buttons for navigation and power buttons for selection. Select "Wipe & Reset".
5. Then select "Wipe Cache" (not "Wipe Data").
6. Confirm the action by selecting Yes.
7. Once completed, select "Reboot to System" to restart.

This method helps if:

• 🐢 The phone is stuck on the logo when turned on.
• 🔄 Applications spontaneously close or issue errors.
• 📱 The system is not updated due to lack of memory.

Method 5: Memory defragmentation (hidden MIUI function)

Even after the cache is cleared, files on the phone can be fragmented, scattered across different parts of memory, which slows down reading/write data. MIUI has a hidden defragmentation feature, but it is not available in all versions of the firmware.

How to start defragmentation:

1. Open the Security app.
2. Go to Optimization. → ⚙️ (gear-up) → Deep cleaning".
3. If there is a “Defragmentation” (or “Optimize storage”) item, tap on it and wait for the process to be completed (it can take 5-20 minutes).

If the item "Defragmentation" is not:

• 📱 Update. MIUI Up to the latest version (in new firmware, the function may appear).
• 🔧 Use third-party apps like Files by Google (there is a defragmentation tool).

💡

Defragmentation is enough to carry out 1 time in 2-3 months. more often - ineffective, less often - will not bring noticeable results.

How to automate cache cleaning?

To avoid manually cleaning the cache, set up automatic optimization:

Option 1. Through “Security”:

1. Open the Security. → ⚙️ → Auto-optimization".
2. Turn on the Auto Clean switch.
3. Select the frequency: “Every week” or “Every month”.

Option 2: With the help of a scheduler (for advanced):

Use the MacroDroid or Tasker app to create a rule:

Condition: Time (e.g. every Monday at 3:00)


Action: Run the cache cleanup via ADB- command:




am broadcast -a android.intent.action.CLEAR_CACHE

⚠️ Note: Auto Cleaning may conflict with some applications (e.g. banking) that require a constant cache to work, in which case add them to the exceptions in the Security settings".

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