"The main problem fixed is slow processing of application state changes.
This may lead to a bootstrapping node not having up to date view on the
ring, and serve incorrect data.
Fixes #2855."
* tag 'tgrabiec/gossip-performance-v3' of github.com:scylladb/seastar-dev:
gms/gossiper: Remove periodic replication of endpoint state map
gossiper: Check for features in the change listener
gms/gossiper: Replicate changes incrementally to other shards
gms/gossiper: Document validity of endpoint_state properties
storage_service: Update token_metadata after changing endpoint_state
gms/gossiper: Process endpoints in parallel
gms/gossiper: Serialize state changes and notifications for given node
utils/loading_shared_values: Allow Loader to return non-future result
gms/gossiper: Encapsulate lookup of endpoint_state
storage_service: Batch token metadata and endpoint state replication
utils/serialized_action: Introduce trigger_later()
gossiper: Add and improve logging
gms/gossiper: Don't fire change listeners when there is no change
gms/gossiper: Allow parallel apply_state_locally()
gms/gossiper: Avoid copies in endpoint_state::add_application_state()
gms/failure_detector: Ignore short update intervals
(cherry picked from commit 044b8deae4)
b12a2e6b08