jihoonson commented on a change in pull request #8879: Add MostAvailableSizeStorageLocationSelectorStrategy URL: https://github.com/apache/druid/pull/8879#discussion_r369299047
########## File path: docs/configuration/index.md ########## @@ -1377,7 +1377,7 @@ These Historical configurations can be defined in the `historical/runtime.proper In `druid.segmentCache.locations`, *freeSpacePercent* was added because *maxSize* setting is only a theoretical limit and assumes that much space will always be available for storing segments. In case of any druid bug leading to unaccounted segment files left alone on disk or some other process writing stuff to disk, This check can start failing segment loading early before filling up the disk completely and leaving the host usable otherwise. -In `druid.segmentCache.locationSelectorStrategy`, one of leastBytesUsed or roundRobin could be specified to represent the strategy to distribute segments across multiple segment cache locations. The leastBytesUsed which is the default strategy always selects a location which has least bytes used in absolute terms. The roundRobin strategy selects a location in a round robin fashion oblivious to the bytes used or the capacity. Note that `if druid.segmentCache.numLoadingThreads` > 1, multiple threads can download different segments at the same time. In this case, with the leastBytesUsed strategy, historicals may select a sub-optimal storage location because each decision is based on a snapshot of the storage location status of when a segment is requested to download. +In `druid.segmentCache.locationSelectorStrategy`, one of leastBytesUsed, roundRobin, random, or mostAvailableSize could be specified to represent the strategy to distribute segments across multiple segment cache locations. The leastBytesUsed which is the default strategy always selects a location which has least bytes used in absolute terms. The roundRobin strategy selects a location in a round robin fashion oblivious to the bytes used or the capacity. The random strategy selects a segment cache location randomly each time among the available storage locations. The mostAvailableSize strategy selects a segment cache location that has most free space among the available storage locations. Note that `if druid.segmentCache.numLoadingThreads` > 1, multiple threads can download different segments at the same time. In this case, with the leastBytesUsed strategy, historicals may select a sub-optimal storage location because each decision is based on a snapshot of the storage location status of when a segment is requested to download. Review comment: What do you think about splitting this paragraph into multiple items? Such as ``` - The leastBytesUsed which ... - The mostAvailableSize strategy ... - The roundRobin strategy ... - The random strategy ... ``` ---------------------------------------------------------------- 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. For queries about this service, please contact Infrastructure at: [email protected] With regards, Apache Git Services --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
