> ## Documentation Index
> Fetch the complete documentation index at: https://docs.prefect.io/llms.txt
> Use this file to discover all available pages before exploring further.
# memory
# `prefect.server.worker_communication.cleanup_queue.memory`
## Classes
### `WorkerCleanupQueue`
Singleton in-memory cleanup queue storage for a single server process.
**Methods:**
#### `ack`
```python theme={null}
ack(self) -> CleanupQueueOperationResult
```
#### `clear`
```python theme={null}
clear(self) -> None
```
#### `enqueue`
```python theme={null}
enqueue(self) -> CleanupQueueMessage
```
#### `expire_leases`
```python theme={null}
expire_leases(self) -> CleanupQueueLeaseExpiryResult
```
#### `read_dead_letter`
```python theme={null}
read_dead_letter(self) -> CleanupQueueDeadLetter | None
```
#### `read_message`
```python theme={null}
read_message(self) -> CleanupQueueMessage | None
```
#### `read_wakeup_sequence`
```python theme={null}
read_wakeup_sequence(self, work_pool_id: UUID) -> int
```
#### `release`
```python theme={null}
release(self) -> CleanupQueueOperationResult
```
#### `renew`
```python theme={null}
renew(self) -> CleanupQueueOperationResult
```
#### `reserve`
```python theme={null}
reserve(self) -> CleanupQueueReservation | None
```
#### `wait_for_wakeup`
```python theme={null}
wait_for_wakeup(self, work_pool_id: UUID) -> CleanupQueueWakeup | None
```
#### `wake_dispatchers`
```python theme={null}
wake_dispatchers(self, work_pool_id: UUID) -> CleanupQueueWakeup
```