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Feng Yuan commented on YARN-6021: --------------------------------- Perhaps I was not clear,if R value is some very wee like 0.00390625,when a queue is 0 minshare(not configed in fair-scheduler.xml) and weight 1 by default. Its fairshare formula is (int)Max(R*weight,minShare) will equal to 0. And this queue is nerver get preempt forever,This is serious. As i think,minshare configation is uncontrollable by now,There is no check in now code if exceed Total. But if base on above situation,if this happened,some 0 minshare queue will suffer. So i suggestion wipe off minshare when compute fairshare. Thanks. > When your allocated minShare of all queue`s added up exceed cluster capacity > you can get some queue for 0 fairshare > ------------------------------------------------------------------------------------------------------------------- > > Key: YARN-6021 > URL: https://issues.apache.org/jira/browse/YARN-6021 > Project: Hadoop YARN > Issue Type: Bug > Components: fairscheduler > Affects Versions: 2.4.0 > Reporter: Feng Yuan > Priority: Critical > > In fair-scheduler.xml,If you config the minshare add up exceed parentQueue`s > fairshare,for root`s childs,fairshare is cluster capacity. > You will found your R value look like below when compute childs fairshares: > 1.0 > 0.5 > 0.25 > 0.125 > 0.0625 > 0.03125 > 0.015625 > 0.0078125 > 0.00390625 > I find this is due to: > double rMax = 1.0; > while (resourceUsedWithWeightToResourceRatio(rMax, schedulables, type) > < totalResource) { > rMax *= 2.0; > } > because resourceUsedWithWeightToResourceRatio will add minShare together. > As i think is really should we bring in minShare when compute fairshare? > My advice is we just consider weight is enough,and minshare's guarantee > will get fulfill when assginContainer! > Hope suggestion! -- This message was sent by Atlassian JIRA (v6.3.4#6332) --------------------------------------------------------------------- To unsubscribe, e-mail: yarn-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: yarn-issues-h...@hadoop.apache.org