MirrorNetworking / MirrorNetworking/Mirror
Memory continuously increases on server during repeated client connect/disconnect cycles
@miwarnec is already working on this.
Since Feb 2, 2026.
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Description
Description
We are seeing unbounded memory growth on a Unity dedicated server using Mirror Networking when clients repeatedly connect and disconnect.
The issue does not happen if no players are connecting. The server remains stable when idle.
To reproduce, we created an automated bot client and a .bat script that continuously logs multiple clients in and out of the server. Under this scenario, memory usage only increases and never goes down.
After ~24 hours of connect/disconnect cycles, memory reached ~7 GB, causing the VPS to be killed by OOM.
Environment
- Unity: 2022.3.55.f1
- Mirror: 96.0.1
- Transport: KCP
- Platform: Linux dedicated server
Observed Behavior
- Memory grows on every connect/disconnect cycle
- Memory is not released after clients disconnect
- Server idle (no connections) does not increase memory
- Memory Profiler shows large growth in Managed Objects → System.Byte[]
Expected Behavior
Memory usage should stabilize or shrink after client disconnects, or there should be a supported way to cap or release internal buffer pools.
Memory Profile Screenshot:
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