Why Xiaomi Redmi 9 is slowing down: hardware and software reasons + 10 ways to speed up your phone

Why is Redmi 9 running slower?

Xiaomi Redmi 9 is one of the most popular budget smartphones of 2020, but even it is not immune to brakes. If your phone starts to hang, slowly open apps or overheat, the reasons can lie in both software failures and hardware wear. Most often users face lags after 2-3 years of operation, when accumulated digital debris and outdated firmware begin to conflict with hardware.

It's important to understand that Redmi 9 is equipped with a MediaTek Helio G80 processor and 3-4 GB of RAM - these characteristics are enough for basic tasks, but not for modern games or dozens of background processes. However, even on a weak hardware, the phone can work quickly if it is optimized correctly. In this article, we will analyze all possible causes of brakes - from overloaded memory to viruses in firmware - and give step-by-step instructions for eliminating them.

Before you start setting up, answer one question:

1. Overloaded memory: the main enemy of speed

The most common reason for brakes is a lack of free space in internal memory. Redmi 9 was released with 32, 64 or 128 GB of drive, but even 128 GB can get clogged with garbage: cache of applications, duplicate photos, unnecessary ones. APK-The critical threshold is less than 10 percent of the free space, and at that volume, the system starts to suffocate because it can't work properly with the file system.

How to check the memory load:

1. Open the settings → About the phone → Memory.
2. If the blue band (system files) is more than 20 GB on a 32-gigabyte model, that's a wake-up call.
3. Click “Clean” next to the “Junk” section.

What takes up the most space:

• 📸 High-resolution photos and videos (especially if enabled) HEIF/HEVC camera-setting).
• 🎮 Cache games (eg Genshin Impact or Call of Duty Mobile can eat 5-10 GB).
• 📥 Downloads — APK-files, archives, documents you haven’t used in a long time.
• 🤖 System cache (/data/dalvik-cache), which accumulates after updates.

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Use cloud services (such as Google Photos or Mi Cloud) to automatically upload photos/video. Configure media compression to High Quality, which will save up to 70% of space.

Background and Autoboot: Who is Stealing Your RAM?

Redmi 9 with 3GB of RAM can’t physically hold 20+ apps at the same time. However, many programs (especially messengers and social networks) are added to the autoboot and run in the background, consuming resources. For example, Facebook or TikTok can eat up to 500MB of RAM even when folded.

How to check and disable unnecessary processes:

1. Go to Settings → Applications → Autoboot.
2. Turn off auto-run for all applications except system ones (e.g. MiuiDaemon or SecurityCenter).
3. In the Settings → Battery → Power Saving Mode, select “Balanced” or “Energy Saving”.

List of the most voracious applications (according to Xiaomi data for 2026):

⚠️ Note: Do not disable autoboot for Google Play Services and Miui System – this can cause disruptions to Google services and branded Xiaomi features.

3.Outdated firmware and MIUI errors

Xiaomi regularly releases updates for Redmi 9, but many users ignore them - and in vain. Older versions of MIUI (below the 14th) contain bugs that lead to:

• 🐢 Slow down animations when opening menus.
• 🔄 Self-resetting.
• 📉 A sharp fall FPS play.
• 🔋 Accelerated battery discharge.

How to update the firmware correctly:

1. Connect to a stable Wi-Fi network (not mobile internet!).
2. Charge your phone to at least 60%.
3. Go to Settings → About the phone → System update.
4. If the update is not located, click on the three dots in the upper right corner and select “Download the latest version”.

If the phone brakes even more after the upgrade, the new MIUI version may not be optimized for your model.

• Make a rollback to the previous version via Fastboot (instruction below).
• Turn off automatic updates in Settings → The phone. → Updating the system → Settings (⚙️) → Auto-update.

4. Viruses and malware: hidden performance killers

Redmi 9 is not immune to viruses, especially if you install apps from third-party sources (not Google Play).

• 🕵️‍♂️ Mining cryptocurrency in the background (for example, through HiddenAds or Joker Trojans).
• 📊 Send your data to the servers of attackers.
• 🔄 Substitute ads in the browser by downloading additional modules.

Signs of infection:

• The phone is heated for no reason (even in standby mode).
• B Settings → The battery is not known to have unknown processes (e.g. com.android.system with a consumption of 30%).
• Advertisements pop up in apps where they haven't been before.

How to check and remove viruses:

1. Install antivirus (recommended Malwarebytes or Dr.Web Light).
2. Start a deep scan (not fast!).
3. Check the list of installed apps in Settings → Apps. Uninstall suspicious ones (such as System Update, Flash Player or Cleaner Pro).
4. Reset network settings: Settings → SIM-maps and mobile networks → Resetting network settings.

⚠️ Note: Some viruses are disguised as system applications (e.g. Android System WebView). Before deleting, check the name in Google - real system applications cannot be removed!

5. Hardware problems: when iron is to blame

If software methods did not help, the cause of the brakes can lie in the physical wear of components. Redmi 9 does not apply to “long-playing” smartphones, and after 3-4 years it often occurs:

Top.-5 brake-cause:

• 🔋 Battery degradation: If the battery capacity has dropped below 70% of its original capacity, the phone starts trottling (forced performance reduction) to save energy. → Battery → Battery status or through AccuBattery.
• 💾 The cheap memory of the eMMC 5.1 in Redmi 9 loses read/write speed over time, manifesting as a long load of applications or “freezes” when scrolling through the gallery.
• 🌡️ CPU overheating. If the phone heats up above 50°C, MediaTek Helio G80 It automatically reduces the frequency, causes: dried thermopaste, dust in the connector or damaged battery.
• 📶 Communications module problems. Wi-Fi/4G-The module can cause constant attempts to reconnect, which loads the processor.
• 🛠️ Damaged charging connector. If the contacts are oxidized, the phone may lose power, leading to sudden performance drops.

How to diagnose hardware problems:

1. Check the temperature through AIDA64 (Sensors section) Normal: up to 45°C in plain, up to 65°C under load.
2. Run a performance test in AnTuTu Benchmark, where scores below 180,000 are a sign of iron wear.
3. Check out the error log: Settings → About Phone → MIUI version (click 5 times) → Menu → Error Log.

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If the phone is only slowing when charging, the problem is most likely in the power supply or cable. Try charging the Redmi 9 with the original 18W RAM - if the lags are gone, replace the accessories.

6. Incorrect system settings: what are you missing?

Many users are unaware that standard MIUI settings can slow down the phone, such as the interface animations on or background data synchronization creating unnecessary loads.

Checklist for settings for acceleration:

Additional advice:

• 🎨 Use lightweight wallpaper (static, no animation) Live wallpaper can consume up to 10% of the CPU.
• 🔊 Turn off vibration when pressed (Settings) → Sound and vibration → Touch vibrations will reduce the load on the clock generator.
• 🌐 B Settings → The Internet and the Internet → Select the data transfer mode only 4G (if you don't 5G). Automatic search is wasting resources.

If you like customization, but the phone is slowing down, try resetting the launcher settings:

1. Click the empty space on the main screen.
2. Select “Home Screen Settings”.
3. Click "Reset settings."

7 Radical methods: reset, firmware, iron replacement

If none of these things worked, it's time to consider extreme measures that will take longer, but often work even on highly outdated devices.

Resuscitation of Redmi 9:

• 🔄 Hard Reset: Deletes all data, but it returns the phone to factory status. How to do it: Turn off the phone. + Volume up before the Mi logo appears. In the Recovery menu, select Wipe Data → Wipe All Data.

Fastboot flashing through Fastboot

Attention:

fastboot flash boot boot.img


fastboot flash system system.img




fastboot flash recovery recovery.img




fastboot reboot

Replacement of thermopaste

Battery replacement

Redmi 9

⚠️ Note: When you are running through Fastboot, use only official images from the site. MIUI Download. Custom firmware (e.g. LineageOS) may not support all of Redmi 9's features (e.g., LineageOS, NFC double-camera).

FAQ: Frequent questions about Redmi 9 brakes