eMMC (embedded MultiMediaCard) is widely used in embedded systems and single board computers (SBCs) like the RK3568 System on Module for storing OS images and application data. But how do you know when your eMMC is failing — before your device stops working entirely?

In this post, I’ll share 5 real-world signs that your eMMC is damaged — based on over a decade of debugging embedded systems in production environments.

🛠️ 1. File System Suddenly Goes Read-Only
If your Linux root file system (/) or data partition unexpectedly becomes read-only, it's often a signal that the eMMC controller has detected a critical internal error. This is a fail-safe mechanism to prevent further corruption.

Debug Tip: Check dmesg | grep mmcblk for I/O error messages or block-level failures.

⚠️ 2. Random Boot Failures or Kernel Panics
Devices that crash randomly on boot — but succeed occasionally — may be accessing bad sectors during the bootloader or kernel loading process. A failing eMMC chip often leads to inconsistent system startup behavior.

Use Case: We've seen this pattern frequently on RK3566/RK3568 SOMs in field-deployed equipment.

🔍 3. Unexpected Application Crashes or Data Corruption
Apps that store logs or configs in /data or /home might crash or behave abnormally when eMMC sectors degrade. You may also notice missing configuration files or SQLite database corruption.

What to look for: File-not-found errors, corrupted databases, or inconsistent app state on reboot.

📈 4. I/O Performance Degradation
If your device's performance gradually slows down, and disk benchmarks (e.g., hdparm, fio) show a drop in write speed, your eMMC may be entering the end of its write/erase lifecycle.

Pro Tip: Regularly benchmark your I/O performance in production builds to spot degradation early.

📉 5. SMART or Health Status Tools Report Failures
Many modern eMMC chips (especially industrial-grade ones) support EXT_CSD registers that reveal health information. If you're using an SoC like RK3568, you can use mmc extcsd read /dev/mmcblk0 to check PRE_EOL_INFO and DEVICE_LIFE_TIME_EST_TYP_A.

Learn more in our RK3568 SBC documentation.

✅ Bonus: How to Prevent eMMC Failures
Use wear leveling and journaling file systems like ext4

Avoid excessive logging to disk (use tmpfs for logs if possible)

Choose industrial-grade eMMC chips

Monitor device health regularly

Schedule periodic backups or snapshotting where applicable

💡 Closing Thoughts
eMMC failure is one of the most common root causes of instability in embedded Linux systems. Recognizing these symptoms early can save your team significant time and cost in field support.

If you're building products based on Rockchip platforms like RK3568 or RK3566, make sure to choose SOMs with reliable eMMC and long-term lifecycle support.

👉 Check out our RK3568 SOM product here — with industrial-grade eMMC and extensive software support.