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# dispatch_source_memorypressure_flags_t

Memory pressure events.

```
typedef unsigned long dispatch_source_memorypressure_flags_t;
```

## Topics

### Memory Pressure Event Flags

[`DISPATCH_MEMORYPRESSURE_WARN`](/documentation/Dispatch/DISPATCH_MEMORYPRESSURE_WARN)

The system memory pressure condition is at the warning stage.

[`DISPATCH_MEMORYPRESSURE_NORMAL`](/documentation/Dispatch/DISPATCH_MEMORYPRESSURE_NORMAL)

The system memory pressure condition has returned to normal.

[`DISPATCH_MEMORYPRESSURE_CRITICAL`](/documentation/Dispatch/DISPATCH_MEMORYPRESSURE_CRITICAL)

The system memory pressure condition is at the critical stage.


---

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