leventov commented on a change in pull request #7154: rename maintenance mode to decommission URL: https://github.com/apache/incubator-druid/pull/7154#discussion_r262276409
########## File path: docs/content/configuration/index.md ########## @@ -803,9 +803,9 @@ Issuing a GET request at the same URL will return the spec that is currently in |`killDataSourceWhitelist`|List of dataSources for which kill tasks are sent if property `druid.coordinator.kill.on` is true. This can be a list of comma-separated dataSources or a JSON array.|none| |`killAllDataSources`|Send kill tasks for ALL dataSources if property `druid.coordinator.kill.on` is true. If this is set to true then `killDataSourceWhitelist` must not be specified or be empty list.|false| |`killPendingSegmentsSkipList`|List of dataSources for which pendingSegments are _NOT_ cleaned up if property `druid.coordinator.kill.pendingSegments.on` is true. This can be a list of comma-separated dataSources or a JSON array.|none| -|`maxSegmentsInNodeLoadingQueue`|The maximum number of segments that could be queued for loading to any given server. This parameter could be used to speed up segments loading process, especially if there are "slow" processes in the cluster (with low loading speed) or if too much segments scheduled to be replicated to some particular node (faster loading could be preferred to better segments distribution). Desired value depends on segments loading speed, acceptable replication time and number of processes. Value 1000 could be a start point for a rather big cluster. Default value is 0 (loading queue is unbounded) |0| -|`historicalNodesInMaintenance`| List of Historical nodes in maintenance mode. Coordinator doesn't assign new segments on those nodes and moves segments from the nodes according to a specified priority.|none| -|`nodesInMaintenancePriority`| Priority of segments from servers in maintenance. Coordinator takes ceil(maxSegmentsToMove * (priority / 10)) from servers in maitenance during balancing phase, i.e.:<br>0 - no segments from servers in maintenance will be processed during balancing<br>5 - 50% segments from servers in maintenance<br>10 - 100% segments from servers in maintenance<br>By leveraging the priority an operator can prevent general nodes from overload or decrease maitenance time instead.|7| +|`maxSegmentsInNodeLoadingQueue`|The maximum number of segments that could be queued for loading to any given server. This parameter could be used to speed up segments loading process, especially if there are "slow" nodes in the cluster (with low loading speed) or if too much segments scheduled to be replicated to some particular node (faster loading could be preferred to better segments distribution). Desired value depends on segments loading speed, acceptable replication time and number of nodes. Value 1000 could be a start point for a rather big cluster. Default value is 0 (loading queue is unbounded) |0| +|`decommissioningNodes`| List of 'decommissioning' historical servers. The Coordinator doesn't assign new segments to these servers and moves segments from the servers at the rate specified by `decommissioningVelocity`.|none| +|`decommissioningVelocity`| Decommissioning velocity indicates what proportion of balancer 'move' operations out of `maxSegmentsToMove` total will be spent towards 'decommissioning' servers by moving their segments to active servers, instead of normal 'balancing' moves. Coordinator takes ceil(maxSegmentsToMove * (velocity / 10)) from servers in maitenance during balancing phase, i.e.:<br>0 - no segments from decommissioning servers will be processed during balancing<br>5 - 50% segments from decommissioning servers<br>10 - 100% segments from decommissioning servers<br>By leveraging the velocity an operator can prevent general servers from overload or decrease decommissioning time instead. Decommissioning can become stalled if there are no available active servers to place the segments.|7| Review comment: I think this description may be confusing. I suggest > Decommissioning velocity determines the maximum number of segments that may be moved away from 'decommissioning' servers non-decommissioning (that is, active) servers during one Coordinator's run, relative to the total maximum segment movements allowed during one Coordinator's run (which, in turn, is determined by the `maxSegmentsToMove` configuration). Specifically, the maximum is ceil(maxSegmentsToMove * (velocity / 10)). For example, if decommissioningVelocity is 0 no segments will be moved away from 'decommissioning' servers. If decommissioningVelocity is 5 no more than ceil(maxSegmentsToMove * 0.5) segments may be moved away from 'decommissioning' servers. By leveraging the velocity an operator can prevent general servers from overload or decrease decommissioning time instead. Decommissioning can become stalled if there are no available active servers to place the segments. The value should be between 0 and 10. The difference in language is that instead of saying "will be spent" and "will be processed", we say "maximum that _may_ be moved", because Coordinator doesn't guarantee and doesn't need to fulfill the "quota". Also removed the phrase "spent towards 'decommissioning' servers" because it may be confusing: we don't do anything "towards" decommissioning servers, rather "away from". ---------------------------------------------------------------- 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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