kfaraz commented on code in PR #14590: URL: https://github.com/apache/druid/pull/14590#discussion_r1264911402
########## docs/configuration/index.md: ########## @@ -961,9 +962,29 @@ Issuing a GET request at the same URL will return the spec that is currently in |`decommissioningMaxPercentOfMaxSegmentsToMove`| Upper limit of segments the Coordinator can move from decommissioning servers to active non-decommissioning servers during a single run. This value is relative to the total maximum number of segments that can be moved at any given time based upon the value of `maxSegmentsToMove`.<br /><br />If `decommissioningMaxPercentOfMaxSegmentsToMove` is 0, the Coordinator does not move segments to decommissioning servers, effectively putting them in a type of "maintenance" mode. In this case, decommissioning servers do not participate in balancing or assignment by load rules. The Coordinator still considers segments on decommissioning servers as candidates to replicate on active servers.<br /><br />Decommissioning can stall if there are no available active servers to move the segments to. You can use the maximum percent of decommissioning segment movements to prioritize balancing or to decrease commissioning time to prevent active servers from b eing overloaded. The value must be between 0 and 100.|70| |`pauseCoordination`| Boolean flag for whether or not the coordinator should execute its various duties of coordinating the cluster. Setting this to true essentially pauses all coordination work while allowing the API to remain up. Duties that are paused include all classes that implement the `CoordinatorDuty` Interface. Such duties include: Segment balancing, Segment compaction, Submitting kill tasks for unused segments (if enabled), Logging of used segments in the cluster, Marking of newly unused or overshadowed segments, Matching and execution of load/drop rules for used segments, Unloading segments that are no longer marked as used from Historical servers. An example of when an admin may want to pause coordination would be if they are doing deep storage maintenance on HDFS Name Nodes with downtime and don't want the coordinator to be directing Historical Nodes to hit the Name Node with API requests until maintenance is done and the deep store is declared healthy for use again. | false| |`replicateAfterLoadTimeout`| Boolean flag for whether or not additional replication is needed for segments that have failed to load due to the expiry of `druid.coordinator.load.timeout`. If this is set to true, the coordinator will attempt to replicate the failed segment on a different historical server. This helps improve the segment availability if there are a few slow historicals in the cluster. However, the slow historical may still load the segment later and the coordinator may issue drop requests if the segment is over-replicated.|false| -|`maxNonPrimaryReplicantsToLoad`|This is the maximum number of non-primary segment replicants to load per Coordination run. This number can be set to put a hard upper limit on the number of replicants loaded. It is a tool that can help prevent long delays in new data being available for query after events that require many non-primary replicants to be loaded by the cluster; such as a Historical node disconnecting from the cluster. The default value essentially means there is no limit on the number of replicants loaded per coordination cycle. If you want to use a non-default value for this config, you may want to start with it being `~20%` of the number of segments found on your Historical server with the most segments. You can use the Druid metric, `coordinator/time` with the filter `duty=org.apache.druid.server.coordinator.duty.RunRules` to see how different values of this config impact your Coordinator execution time.|`Integer.MAX_VALUE`| +|`maxNonPrimaryReplicantsToLoad`|The maximum number of replicas that can be assigned across all tiers in a single Coordinator run. This parameter serves the same purpose as `replicationThrottleLimit` except this limit applies at the cluster-level instead of per tier. The default value essentially means that there is no limit on the number of replicas assigned per coordination cycle. If you want to use a non-default value for this config, you may want to start with it being `~20%` of the number of segments found on the Historical server with the most segments. Use the Druid metric, `coordinator/time` with the filter `duty=org.apache.druid.server.coordinator.duty.RunRules` to see how different values of this config impact your Coordinator execution time.|`Integer.MAX_VALUE` (i.e. no limit)| +##### Smart segment loading +The `smartSegmentLoading` mode of the Coordinator makes configuring it for segment loading and balancing much easier. +In this mode, the Coordinator does not require the user to provide values of the following parameters and computes them automatically instead. +If provided, the values are simply ignored. Review Comment: Done. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. 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