Zombies appearing at shutdown

[tsarajar]

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Description
From discussion at https://forum.opennebula.io/t/zombie-polling-interval-and-mismatch/12440

Shutting down and deleting VMs causes zombies as monitoring and SYNC_STATE don't happen immediately.
It will falsely report zombies, even though there aren't any, until the next SYNC_STATE finds out the true nature of things.

To Reproduce
Terminate a VM and start looking at host zombies.

Expected behavior
There shouldn't be any zombies.

Details

• Affected Component: Sunstone and Scheduler?
• Hypervisor: KVM
• Version: 6.8.0

Additional context

Progress Status

• Code committed
• Testing - QA
• Documentation (Release notes - resolved issues, compatibility, known issues)