How to increase the performance of Xiaomi Redmi Note 9: from cleaning the cache to hidden settings MIUI

Why does Redmi Note 9 start to brake and how to fix it?

Xiaomi Redmi Note 9 smartphone based on MediaTek Helio processor G85 And 4GB of RAM initially shows great performance for its price segment, but over time, even this "workhorse" begins to slow down: applications open long, animation twitches, and in games falls down. FPS. The fault is the features of the firmware MIUI, cache and background processes that eat up resources.

In this article, we will discuss 12 proven ways to speed up the Redmi Note 9 – from basic (cleaning up memory and disabling animation) to advanced (setting up the processor cores and optimization). MIUI All methods are tested on current versions of firmware and do not require root rights, except for one exception (about it - at the end of the article).

Important: if your smartphone began to slow down after updating to MIUI 14+, The problem may be in the new energy saving policy, in which case the reset to the factory settings with data storage will help (for this, see the section on "Safe discharge»).

1. Cleaning the system: remove garbage and cache

The first step to speed up is to free up memory. 9 s 64/128 GB of storage space directly affects the speed of operation. 10% In memory, the system begins to “suffocate».

Start with the built-in cleaning tool:

1. Go to Settings → About the phone → Memory.
2. Press Clean (blue button at the bottom).
3. Select Deep Cleanup and confirm the removal of the app cache.

For more thorough cleaning, use the side of the utility:

• 🧹 SD Maid – deletes residual files after uninstalling applications.
• 🗑️ Files by Google – Finds duplicates and large, unnecessary files.
• 🔍 CCleaner – Clears Dalvik cache (requires root for full functionality).

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After cleaning the cache, restart the phone – this will allow the system to recollect optimized data for frequently used applications.

Pay attention to the folder. DCIM/.thumbnails — Here are the photos and videos that can be used up to 1–2 GB: It can be safely removed (miniatures will be restored automatically).

Optimization MIUI: Disable unnecessary functions and animations

MIUI She's known for her abundance of background processes and visuals that steal resources»:

Step 1. Remove the interface animation

1. Activate Developer Mode: Settings → About Phone → MIUI version (click 7 times).
2. Back to Settings → Additionally. → For developers.
3. Find the items: Window animation scale → Disable the animation scale of the transition → Disable the animation duration of animation → Disable

Step 2. Turn off background activity

• 🚫 Settings → Annexes → Application management → Autorun – disable autorun for unnecessary programs (especially social networks and instant messengers).
• 🔄 Settings → Battery → Energy saving regime → Choose Balanced (High Performance Mode Often Leads to Overheating).
• 📵 Settings → Connections → Mobile network → Network mode → Just set it up. LTE (if 5G It is not necessary, its module consumes extra resources).

Step 3: Setting up Light Mode

V MIUI 12+ And then there's the hidden Lite mode, which simplifies the interface and reduces the load on the processor:

Settings → Special features → Lite mode

This mode disables unnecessary widgets, simplifies animation and reduces RAM consumption by 15-20%.

3. Performance setting for games (Game Turbo)

If you use Redmi Note 9 for gaming (PUBG Mobile, Call of Duty, Genshin Impact, be sure to configure the built-in Game Turbo.This feature optimizes resource allocation and blocks notifications during gameplay.

How to turn on and configure Game Turbo:

1. Open Settings → Special features → Game Turbo
2. Activate the switch at the top.
3. In the Game Settings section, select: 🎮 Productivity → Maximum 📶 Network → Priority of traffic for gaming 🔋 Energy conservation → Disable restrictions

Added games

For an extra boost FPS play:

• 🖥️ Set the screen resolution on 720p (HD+) In the game settings (this will reduce the load on the GPU Mali-G52).
• 🔄 Enable Performance Mode in the game graphics settings (if there is such a point).
• ⚡ Use it. GFX Tool (requires root) for overclocking GPU up to 950 MHz (standard - 820 MHz).

Important: For long gaming sessions, monitor the temperature of the processor if it exceeds 65.°C, use a cooling stand or take a break – trottling (automatic frequency reduction) can negate all optimizations.

4. Optimization of autoboot and background processes

One of the main reasons for the brakes is the applications that start at the start of the system and hang in the background. On the Redmi Note 9 with 4 GB of RAM, this is critical: even 5-6 background processes can eat up to 50% of RAM.

How to turn off autoboot:

1. Go to Settings → Applications → Application Management.
2. Select an app (like Facebook or AliExpress).
3. Press Autostart and turn off the slider.
4. Repeat for all unnecessary programs.

List of the most voracious apps (turn off their auto-run first):

• 📱 Facebook and Facebook Messenger – consume up to 300 MB of RAM in the background.
• 💬 Viber, WhatsApp – keep a constant connection to servers.
• 🛒 AliExpress, Wildberries – Update directories in the background.
• 🎵 Yandex Music, Spotify – cache tracks even when not playing.

To control your background, use Greenify (requires root to work without restrictions), which freezes unnecessary services to keep them from waking up.

After cleaning up the boot, check the free RAM in Settings → The phone. → Memory. → RAM: Ideally, 1.5–2 GB should be free after the reboot.

5. Update firmware and reset to factory settings

If the brakes appeared after the update MIUI, The problem may be in the "curve" update, in which case a clean firmware installation or resetting will help.

Option 1: Update via Recovery (without loss of data)

1. Download the latest stable firmware for Redmi Note 9 (merlin) from the official Xiaomi website.
2. Rename the file to update.zip and place it in the root of the phone’s memory.
3. Go to Settings. → The phone. → Updating the system → press the three dots at the top. → Select a firmware file.
4. Select update.zip and confirm the installation.

Option 2: Secure reset (saves files but resets settings)

1. Go to Settings → About the phone → Reset settings.
2. Select Settings Reset (Do not delete all data!).
3. Confirm the action. The phone will reboot, but the photos and documents will remain.

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If, after updating, MIUI 14+ The lags have appeared, try to roll back on MIUI 13 via Fastboot. Instructions are on the forum 4PDA Theme of the Redmi Note 9.

Table: Comparison of discharge methods

If the reset didn’t help, the problem could be the wear and tear of the flash memory (especially if the phone was actively used 2).+ In this case, only replacing the drive in the service center will help.

Overclocking of the processor and GPU (Only for experienced users)

To maximize productivity, you can overclock MediaTek Helio G85 graphical accelerator Mali-G52. This method requires root rights and can shorten the life of a chip if the settings are wrong.

What can be dispersed:

• 🔥 Central processing unit (CPU): Standard frequencies - up to 2.0 GHz, you can raise to 2.2 GHz (but not higher!).
• 🖥️ Graphics processor (GPU): standard - 820 MHz, acceleration to 950 MHz gives +10–15 FPS play.
• 💾 RAM (RAM): Increase the exchange rate from 1600 MHz to 1800 MHz.

Instructions for overclocking (root required):

1. Install Kernel Adiutor or FrancoKernel Manager from Google Play.
2. In the section CPU Max. frequency of Big cores: 2200 MHz Max. frequency of Little cores: 1800 MHz Governor: performance (for games) or ondemand (for everyday use).

GPU

950 MHz

Save the settings and restart the phone.

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Before overclocking, check the temperature of the processor in simple (should not be higher than 40).°If the phone is warm even without load, overclocking is contraindicated!

Risks of overclocking:

⚠️ Attention: Overclocking reduces the life of the processor and can lead to trottling (automatic frequency reduction when overheated).If after overclocking the phone starts to accidentally reboot or turn off, return the standard settings.

Use temperature and frequency control AIDA64 or CPU Monitor, if the temperature is above 70°C under load, reduce frequencies by 100-150 MHz.

7.Alternative firmware: when MIUI is no longer salvageable

If all optimization methods have failed, consider installing custom firmware. The Redmi Note 9 works well:

• 🤖 LineageOS – “naked” Android without unnecessary services Xiaomi.
• ⚡ Pixel Experience – firmware with Google Pixel interface and optimized kernel.
• 🔄 Havoc-OS – flexible firmware with many performance settings.
• 🎯 MIUI Pro - modified version MIUI free of advertising and unnecessary services.

The advantages of custom firmware:

• ✅ No built-in advertising and unnecessary services Xiaomi.
• ✅ Faster security updates (monthly patches from Google).
• ✅ Ability to fine-tune the kernel and task scheduler.

Cons:

• ❌ Loss of warranty (if it is still valid).
• ❌ The risk of “bricking” the phone when installed incorrectly.
• ❌ Certain functions (e.g, IR-blaster) may not work properly.

To install custom firmware will require:

1. Unlock bootloader (officially via Mi Unlock Tool)
2. Install the custom TWRP recavator.
3. Backup the current firmware.
4. Swipe new firmware and GApps (Google services).

⚠️ Warning: Check compatibility with Redmi Note 9 (merlin) before firmware is installed. Installing firmware from another model will cause the phone to fail!

8 Hardware Methods: When Software Optimization Does Not Help

If the software methods do not give a result, the problem may lie in the "iron":

Frequent hardware causes of brakes:

• 🔋 Worn-out battery – when it degrades below 80% of capacity, the phone begins to limit performance.
• 💾 Damaged flash memory – broken sectors slow down reading/write data.
• 🌡️ Overheating – dust in the radiator or dried thermopaste leads to trottling.
• 📶 Bad antenna contact – the phone spends resources searching for the network.

How to check for "iron":

1. Battery: Install AccuBattery and check for wear. If the capacity is below 3,000 mAh (originally 5,020 mAh), replace the battery.
2. Flash memory: Run the test in AIDA64 (storage → Read/write test: Read speed should be at least 200 MB/s.
3. Overheating: If the phone is heated above 45°C in plain, disassemble it and clean it from dust (or contact the service).

If the battery is a problem, it will cost 1500-2500 to replace it. ₽ (Replacing flash memory is best left to a service center, a complex operation that requires soldering equipment.

For a temporary solution (if there is no possibility of repair) you can:

• 🔌 Use the phone from charging (if the battery is a problem).
• ❄️ Cool it with a fan or cooling stand.
• 📴 Disable the mobile network and use only Wi-Fi (if the problem is in the communication module).

FAQ: Frequent questions about the Redmi Note 9 acceleration