libmuscle.manager.deadlock_detector module

class libmuscle.manager.deadlock_detector.DeadlockDetector[source]

Bases: object

The DeadlockDetector attempts to detect when multiple instances are stuck waiting for each other.

This class is responsible for handling WAITING_FOR_RECEIVE, IS_DEADLOCKED and WAITING_FOR_RECEIVE_DONE MMP messages, which are submitted by the MMPServer.

When a deadlock is detected, the cycle of instances that is waiting for each other is logged with FATAL severity.

is_deadlocked(instance_id: str) → bool[source]

Check if the provided instance is part of a detected deadlock.

This method can be called from any thread.

waiting_for_receive(instance_id: str, peer_instance_id: str, port_name: str, slot: int | None) → None[source]

Process a WAITING_FOR_RECEIVE message from an instance.

This method can be called from any thread.

Parameters:

  • instance_id – ID of instance that is waiting to receive a message.

  • peer_instance_id – ID of the peer that the instance is waiting for.

  • port_name – Name of the input port.

  • slot – Optional slot number of the input port.

waiting_for_receive_done(instance_id: str, peer_instance_id: str, port_name: str, slot: int | None) → None[source]

Process a WAITING_FOR_RECEIVE_DONE message from an instance.

This method can be called from any thread.

Parameters:

  • instance_id – ID of instance that is waiting to receive a message.

  • peer_instance_id – ID of the peer that the instance is waiting for.

  • port_name – Name of the input port.

  • slot – Optional slot number of the input port.