(the post is automatically translated by AI)

Introduction

A memory leak occurs when allocated memory is never freed. While it doesn’t necessarily cause immediate crashes, a leak gradually reduces the available memory, degrading system performance over time. In severe cases, it can lead to unpredictable errors or even security vulnerabilities 1.

Memory: “Hmm? Something smells.”

One of the most common causes of memory leaks is forgetting to free dynamically allocated memory — for instance, calling new on the heap and never calling delete. The unpredictable timing of when this causes problems makes debugging quite difficult.

In Unity, when a memory leak occurs, the console typically shows:

A Native Collection has not been disposed, resulting in a memory leak. Enable Full StackTraces to get more details.

Without further information, this error message alone is not very useful for pinpointing the source of the leak.

How to Enable Full Stack Traces

Following the hint in the Unity console, we need to enable Full StackTraces for more details.

  1. Install the Jobs package

    1. Go to Window > Package Manager
    2. Set the package source to Unity Registry
    3. Search for the Jobs package
    4. Click Install
    5. After installation, a Jobs menu should appear in the menu bar. If it doesn’t, go back and confirm the installation succeeded.

  2. Enable leak detection

    1. Select Jobs > Leak Detection from the menu bar
    2. Change the setting from the default On to Full Stack Traces (Expensive)

  3. Re-run your project

Now, when a memory leak occurs, the Unity console will show the exact location of the leak, making it much easier to track down and fix.

Conclusion

Memory leaks stem from improper memory management and can cause unpredictable errors that are hard to debug — especially in code you didn’t write yourself. This article provides a quick method to pinpoint memory leaks in Unity. Hopefully, the next time you encounter this issue, you’ll be able to resolve it faster!