Buffer magazine on Xiaomi: hidden logs that slow down your smartphone

Have you ever noticed that even after you clean your cache completely and delete your files, your Xiaomi keeps on slowing down? It may be because of a little-known log buffer, which is a hidden partition that stores debugging information that the manufacturer and developers use to diagnose bugs, but over time it grows, taking up precious space and slowing down the device.

Unlike a regular app cache, the log buffer is not cleaned by standard MIUI tools. Its contents accumulate over the years: system process logs, kernel errors, application crash data, and even network connection information. In this article, we will explain what a log buffer on Xiaomi is, how to find it, safely clean it and prevent refilling - without the risk of damaging the firmware or losing data.

What is a magazine buffer and why is it needed?

Log buffer is a special memory area in Xiaomi smartphones designed to store logical logs about the operation of the system.

• 📱 Android core – critical errors, driver failures, overheating data;
• 🔄 System services – information about start/stop processes, memory usage;
• 📡 Communication modules – logs of connections to Wi-Fi, Bluetooth, cellular networks;
• 🛠️ Applications – debugging information from developers (if debugging mode is enabled).

By default, the log buffer is fixed in size (usually 1-4 MB), but on some Xiaomi models (such as the Redmi Note 10 Pro or POCO F3) it can expand to 10-20 MB. The main problem is that these logs are never cleared automatically, even after resetting. They continue to accumulate until they fill the allocated space, which leads to:

• ⚠️ Slowing down the interface MIUI;
• ⚠️ Increased response time of the system;
• ⚠️ Unreasonable battery discharge (due to constant log recording).

⚠️ Note: The log buffer does not match the folder /data/log It can't be cleared through Settings. → The storage room requires special commands or engineering menus to access it.

The manufacturer leaves the log buffer included even in the retail versions of smartphones, as this data is critical for debugging during warranty repairs.

How to check if the log buffer is full on your Xiaomi

Before you clean the buffer, you should make sure it's really full. There are two reliable ways to do this.

Method 1: Through the Engineering Menu (without root)

This method works on most Xiaomi models, including the Redmi 9, POCO X3 and Mi 11:

1. Open the phone application;
2. Enter the combination: ##4636##;
3. Select Usage Statistics (Usage Statistics)
4. Scroll down to the Log buffer section – here will be the percentage of the fill.

If the value is greater than 80%, the buffer needs cleaning. Some firmware (e.g. MIUI 14) may not have this item, so use the second method.

Method 2: ADB (for advanced users)

If the engineering menu is not available, connect the smartphone to the PC and execute the command:

adb shell dumpsys -t 10 logcat -b all -d | grep "Buffer stats"

In the answer, look for lines like main: 95% (1.8MB/2MB) — that's the current buffer state. If the numbers are close to 100%, it's time to act.

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On models with MIUI 13+, you can use the Device Care app (in the Warehouse → Deep Clean section), but it only cleans a part of the logs, not the entire buffer.

How to Clean a Magazine Buffer on Xiaomi: 3 Working Methods

Cleaning the log buffer is a precautionary procedure, and doing the wrong thing can cause you to lose debugging data that you might need when you contact the service center, but if you are sure you don't need it, follow the instructions below.

Method 1: Engineering menu (the safest)

Suitable for most devices without root rights:

Enter ##4636### in dialer | Go to Usage statistics | Find Log buffer |Tap Clear log buffer |Confirm action-->

Once cleaned, restart your smartphone. This method only resets current logs without affecting system files.

Method 2: ADB (for experienced users)

If the engineering menu is not available, use the command:

adb shell logcat -b all -c

To clean all buffers (including radio modules) completely, do:

adb shell logcat -b events -b radio -b main -c

⚠️ Attention: On some firmware (MIUI 12.5 and below) these commands may not work due to security limitations, in which case a temporary root license will be required.

Method 3: Through applications (requires root)

Applications like Logcat Reader or MTK Engineering Mode (for MediaTek devices) allow you to view and clean logs manually, but they require:

• 🔓 Root access;
• 📱 Unlocked bootloader (bootloader);
• 🛡️ Unplugged. MIUI Optimization (in the settings for developers).

Use this method only if the first two do not work.

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Cleaning the log buffer does not delete user data (photos, messages, applications), but can erase error logs that are useful when diagnosing problems in the service center.

Why the journal buffer fills up quickly: the main reasons

If the log buffer fills up too quickly (for example, in a few days), it indicates systemic problems.

On devices with Qualcomm Snapdragon processors (such as Xiaomi 12T or POCO F4), the log buffer fills up faster due to the detailed recording of data on communication modules (5G, Wi-Fi 6). If you do not use debugging functions, it is recommended to disable log recording completely.

How to turn off log recording forever (for power users)

If you don't plan on going to the service center, you can turn off log logging completely, which will free up space and reduce the load on the storage.

Method 1: Through ADB (without root)

Follow the command:

adb shell setprop persist.logd.size 0

Then reboot the device. This will set the buffer size to 0 KB, effectively turning off the recording.

Method 2: Through editing build.prop (requires root)

Open the file /system/build.prop and add the following lines:

persist.logd.size=0


ro.logd.size=0

Save the changes and reboot. After that, the logs will stop writing.

⚠️ Note: Disabling logs may interfere with some system utilities (e.g, MIUI If you have problems with updates after that, return the settings back.

Frequent errors when working with the magazine buffer

Many users make critical mistakes when trying to clear or disable the log buffer.

• 🚫 Delete files manually through Root Explorer – this can damage the system logs needed to work MIUI;
• 🚫 Use rm commands -rf /data/log — This will not delete the buffer, but the folder with user logs;
• 🚫 Disable logs on devices with custom firmware - this can lead to unstable work;
• 🚫 Ignoring overflow warnings – prolonged neglect leads to system slowdown.

If the log is refilled in a few hours after cleaning the buffer, it is a sign of a hardware problem (for example, a flash memory malfunction).

1. Check the health of the drive through ADB with the adb shell dumpsys diskstats command;
2. Reset the settings to factory (Settings → About the phone → Reset settings);
3. Contact the service center if the problem persists.

FAQ: Answers to Frequent Questions About Xiaomi Magazine Buffer