Why Android 9 is slow and how to fix it: a complete guide

Owners of smartphones on Android 9 Pie often encounter a situation where the device begins to “think”, applications open with a delay, and the interface animation twitches. Moreover, the problem occurs even on the flagships of 2018–2019 (Samsung Galaxy S9, OnePlus 6T, Xiaomi Mi 9), not to mention budget models. In this article we will analyze unique features of Android 9 that cause slowdownsand also give specific recommendations for optimization - from simple settings to radical measures.

It is important to understand: slowdowns are not always associated with “aging” of the hardware. More often, software conflicts, update errors, or incorrect operation of system services are to blame. For example, in Android 9 a function appeared, which was supposed to extend autonomy, but in practice sometimes leads to an artificial limitation of the performance of background processes. Next is a detailed analysis of the reasons and solutions. Adaptive Battery, which was supposed to extend autonomy, but in practice sometimes leads to artificially limiting the performance of background processes. Below is a detailed analysis of the reasons and solutions.

1. Overloading the system with background processes

One ​​of the key features Android 9 Pie is aggressive management of background tasks. The system tries to save battery power by pausing applications, but it often does this too zealously. As a result:

• 📱 Messengers (WhatsApp, Telegram) stop receiving notifications in a timely manner.
• 🎵 Music players (Spotify, YouTube Music) freeze when switching tracks.
• 🔄 Data synchronization (mail, cloud services) occurs with a delay.

To check which applications are consuming resources, go to in Settings → Applications and notifications → Memory usage. If there are apps in the list marked “Works in the background,” you should limit them manually.

Also in Android 9 a mechanism has appeared App Standby Bucketsthat distributes applications into activity categories. If your messenger is in the “Rarely Used” category, the system will limit its operation. You can fix this using the ADB command:

adb shell cmd appops set  RUN_ANY_IN_BACKGROUND allow

2. Memory fragmentation and cache errors

Over time internal memory the smartphone becomes filled with temporary files, application cache and fragmented data. This problem is aggravated by the nature of the file system used by many manufacturers. Symptoms: Android 9 this problem is made worse by the nature of the file system F2FS, which is used by many manufacturers. Symptoms:

• 🐢 Slowdown when opening the gallery or camera (long preview loading).
• 🔄 "Freezes" when switching between applications.
• 📉 A sharp drop in free space (for example, with 10 GB to 1 GB for no apparent reason).

The first step is clearing the system application cache. To do this:

1. Go to Settings → Storage → Cache data.
2. Click “Clear cache” (not to be confused with “Clear data”!).
3. Restart the device.

If the problem persists, it is worth considering memory defragmentation. On Android 9 this can be done through ADB or specialized utilities like SD Maid (requires root access). However, be careful: not all firmware supports this function.

⚠️ Attention: On some devices (Huawei, Honor), after clearing the cache, the firmware region may be reset. Before the procedure, check the region settings in Settings → System → Language and input.

3. Conflicts after updating from Android 8 (Oreo)

Many users encounter slowdowns after upgrading from Android 8 to 9. The reason is incomplete compatibility of old settings with the new system. Typical errors:

• 🔧 Conflicts in the file build.prop (for example, incorrect parameters ro.surface_flinger.max_frame_buffer_acquired_buffers).
• 📦 Residual files from old versions of applications that were not deleted during the upgrade.
• 🔄 Incorrect operation of ART (Android runtimes) that did not optimize applications after update.

To fix this, follow these steps:

1. Go to Settings → System → Reset settings → Reset application settings (this will not delete your data, but it will reset permissions and default settings).
2. Clear service data Google Play and Google Services Framework in Settings → Applications.
3. Reboot the device and wait for the application optimization to complete (may take up to 10 minutes).

If the brakes remain, it is worth considering manually reset the Dalvik/ART cache. To do this:

1. Turn off the smartphone.
2. Hold the combination of buttons to enter Recovery (usually Power + Volume Up).
3. Select item Wipe cache partition.
4. Restart the device.

4. animation

Android 9 Pie implemented a new interface rendering system - SurfaceFlinger, which was supposed to improve the smoothness of animation. However, on some devices (especially with chips Mediatek Helio or Qualcomm Snapdragon 6xx) this led to the opposite effect:

• 🖥️ “Ragged” transitions between screens.
• 🎮 Slowdown in games (even in simple ones, like Candy Crush).
• 🔳 Artifacts when scrolling lists (for example, in Instagram or Twitter).

Solutions:

1. Disable interface animation:
   • Activate Developer mode (click on Build number 7 times in Settings → About phone).
   • Go to Settings → System → For developers.
   • Set the values:
     • Window Animation → Disable or 0.5x.
     • Transition Animation → Disable.
     • Animator Duration → Disable.

Reset graphics settings:

• In the same menu For developers find Reset GPU settings.
• Confirm reset and reboot device.

If the problem persists, check CPU temperature using applications like AIDA64. Overheating (above 60°C) can cause throttling (automatic performance reduction).

5. Viruses and malware

In Android 9 virus protection has been enhanced thanks to the built-in scanner Google Play Protect, but some malware still slips through. They can:

• 🕵️‍♂️ Steal CPU resources for cryptocurrency mining.
• 📊 Load ads in the background (even when the screen is off).
• 🔗 Redirect traffic through proxy servers, slowing down Internet.

How to check:

1. Open Settings → Google → Security → Google Play Protect and run a scan.
2. Install a third-party antivirus (Malwarebytes, Bitdefender) and scan the system.
3. Check the list of installed applications for suspicious ones (especially with rights Administrator or Accessibility).

Pay attention to applications with names like:

• com.system.update (fake updates).
• com.android.helper (mining bots).
• com.clean.master (fake optimizers).

⚠️ Attention: Some viruses disguise themselves as system services (for example, Android System WebViewBefore deleting, check the name of the package in Google - real system applications do not have reviews in Play). Market.

6. Lack of random access memory (RAM)

Android 9 Pie more demanding on RAM than previous versions. If your device has less than 3 GB of RAM, the system begins to actively use swap (swap file), which leads to slowdowns. Symptoms:

• 🔄 Applications reload when returning to them (for example, Chrome opens the page again).
• 📱 The interface “freezes” for 2-5 seconds when opening multitasking.
• 🎮 Games crash with an error Out of Memory.

Solutions:

Problem	Solution	Root required?
Not enough free space RAM	Disable unnecessary system services via Settings → Applications	No
Frequent restart of applications	Increase the limit of background processes in Settings → For developers → Limit of background processes	No
Lack of RAM for games	Use utilities like Game Booster (for Xiaomi) or GFX Tools	Sometimes
Swap file is overloaded	Disable zRAM via ADB or kernel	Yes

For devices with 2–3 GB RAM it is recommended:

• 📵 Disable automatic application updates in Google Play.
• 🚫 Use “light” versions of applications (Facebook Lite, Messenger Lite).
• 🔄 Regularly reboot your smartphone (every 1-2 days).

How to check the actual RAM usage?

Open AIDA64 → System → Memory. If the section Used RAM is constantly more than 80%, your device does not have enough RAM.

7. Hardware problems: battery and storage

If software methods do not help, the cause of the brakes may lie in hardware faults:

• 🔋 Worn out battery (capacity below 70%) leads to throttling of the processor.
• 💾 Damaged flash memory (bad blocks) causes read/write delays.
• 🔌 Faulty power controller limiting performance.

How diagnose:

1. Battery:
   • Install AccuBattery and check Battery health.
   • If the capacity is below 70%, replace the battery.

Storage:

• Run the test in AIDA64 (Storage → Read/write test).
• If the speed is below 30 MB/s, the memory may be damaged.

For a temporary solution you can:

• 🔋 Calibrate the battery (discharge to 0%, charge to 100% without interruption).
• 💾 Transfer part of the data to an SD card (if supported Adoptable Storage).

⚠️ Attention: On devices with UFS 2.1 (for example Samsung Galaxy S9) memory corruption can lead to complete loss of data. If you suspect bad blocks, immediately make a backup copy!

FAQ: Frequently asked questions about Android 9 brakes

Is it possible? roll back from Android 9 to Android 8 if the brakes cannot be fixed?

Technically yes, but:

• 🔙 You need official firmware Android 8 for your model (you can find it on XDA Developers or 4PDA).
• 🔓 You will need to unlock the bootloader (on some devices this will reset all data).
• ⚠️ The warranty will be void and some features (for example Digital Wellbeing) will stop working.

We recommend that you first try all the software methods from the article.

Will resetting to factory settings help?

In 80% of cases, yes. Reset deletes:

• 🗑️ Incorrect system settings.
• 🧹 Residual files from old updates.
• 🦠 Hidden viruses (if they are not built into the firmware).

But before resetting:

1. Make a backup via Google Drive or Titanium Backup (root required).
2. Write down the IMEI (dial *#06#).
3. Make sure you have access to the Google account linked to the device (after reset you will need confirmation).

Why did the battery drain quickly after updating to Android 9?

This is due to:

• 🔍 Function Adaptive Battery, which learns to recognize your habits (the first 2-3 days the consumption will be high).
• 🔄 Background optimization of applications (the system scans their activity).
• 📡 Increased work Google Play Services for new functions (for example, App Actions).

Solution:

1. Wait 3-5 days - consumption returns to normal.
2. Disable Adaptive Battery in Settings → Battery → Adaptive battery.
3. Limit background activity for unnecessary applications.

Which applications most often cause slowdowns on Android 9?

Top 5 “gluttonous” applications:

1. Facebook (and its clones: Facebook Lite, Messenger) - constantly running in the background.
2. Instagram - loads the processor when scrolling the tape.
3. UC Browser / Opera Mini —contain hidden mining modules.
4. Clean Master / DU Speed Booster —they themselves consume resources under the guise of optimization.
5. PUBG Mobile / Call of Duty Mobile —overheat the processor on weak devices.

Solution: replace them with alternatives (Hermit for social networks, Bromite instead of Chrome) or limit background activity.

Is it possible to speed up Android 9 without root access?

Yes! Here's what really helps:

• 🛠️ Disabling animation (see section 4).
• 🧹 Clearing the cache via Recovery (does not require root).
• 🔧 Using Developer Options to limit background processes.
• 📱 Installing light firmware (for example, LineageOS without GApps).

Root is needed only for:

• Removing system applications (bloatware).
• Changing kernel parameters (for example, CPU governor).
• Using Xposed Framework for deep customization.

💡

If none of the methods helped, the problem may be in the hardware (memory chip wear, damage to the motherboard). In this case, contact a service center.