Conductor appears to be deadlocked

[patkivikram]

Checklist

• [ x] I have included information about relevant versions
• [ x] I have verified that the issue persists when using the master branch of Faust.

Steps to reproduce

Run the latest version 0.6.13 under load. After a certain time, the faust app stops processing all incoming messages

The issue appears to be with the call to

await self.wait_first(callback(message), self.suspend_flow.wait())

in faust/transport/consumer.py

Versions

• Python version 3.8
• Faust version 0.6.13
• Operating system
• Kafka version
• RocksDB version (if applicable)