515b53d297
This change fixes two possible race conditions in SLM related to how local master changes and cluster state events are observed. When implementing the `LocalNodeMasterListener` interface, it is only recommended to execute on a separate threadpool if the operations are heavy and would block the cluster state thread. SLM specified that the listeners should run in the Snapshot thread pool, but the operations in the listener were lightweight. This had the side effect of causing master changes to be delayed if the Snapshot threads were all busy and could also potentially cause the `onMaster` and `offMaster` calls to race if both were queued and then executed concurrently. Additionally, the `SnapshotLifecycleService` is also a `ClusterStateListener` and there is currently no order of operations guarantee between `LocalNodeMasterListeners` and `ClusterStateListeners` so this could lead to incorrect behavior. The resolution for these two issues is that the SnapshotRetentionService now specifies the `SAME` executor for its implementation of the `LocalNodeMasterListener` interface. The `SnapshotLifecycleService` is no longer a `LocalNodeMasterListener` and instead tracks local master changes in its `ClusterStateListner`. Backport of #59801 |
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| multi-cluster | ||
| multi-node | ||
| rest | ||
| with-security | ||
| build.gradle | ||