Performance tuning
Global · server
integer
max_backlog
Size of the kernel accept queue for pending connections.
- Config key
max_backlog- Scope
- Global · server
- Type
- integer
- Default
- none
The maximum number of established-but-not-yet-accepted connections the kernel will queue. A large backlog absorbs connection bursts without refusing clients; too small and spikes get dropped during the SYN flood of a traffic surge.
⚡High-traffic edges
Sample configs use 100000 for busy front-ends. Pair a large backlog with enough worker capacity to actually drain it.
max_backlog = 100000