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Daryn Sharp commented on HDFS-14403: ------------------------------------ {quote}if you enable the cost-based version, you still make use of the counter-based version ({{getAndIncrementCallCounts()}}, so the costs will be off (the stored value will be cost + 1 for each call). {quote} Very astute! :) I initially shorted out the update on queue insertion but later figured it was ok to charge the user a tiny amount since readers can reject the call (call queue overflow, etc) and that load isn't "free" especially if the abusive user is flooding the NN. > Cost-Based RPC FairCallQueue > ---------------------------- > > Key: HDFS-14403 > URL: https://issues.apache.org/jira/browse/HDFS-14403 > Project: Hadoop HDFS > Issue Type: Improvement > Components: ipc, namenode > Reporter: Erik Krogen > Assignee: Christopher Gregorian > Priority: Major > Labels: qos, rpc > Attachments: CostBasedFairCallQueueDesign_v0.pdf, > HDFS-14403.001.patch, HDFS-14403.002.patch, HDFS-14403.003.patch, > HDFS-14403.branch-2.8.patch > > > HADOOP-15016 initially described extensions to the Hadoop FairCallQueue > encompassing both cost-based analysis of incoming RPCs, as well as support > for reservations of RPC capacity for system/platform users. This JIRA intends > to track the former, as HADOOP-15016 was repurposed to more specifically > focus on the reservation portion of the work. -- This message was sent by Atlassian JIRA (v7.6.3#76005) --------------------------------------------------------------------- To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org