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Benedict edited comment on CASSANDRA-6746 at 3/12/14 7:40 PM: -------------------------------------------------------------- What makes you say we'll blow away our hot cache on flush? Note that the variable is poorly named, and in fact only provides populateOnFlush => !skipIOCache, i.e. if true we do not explicitly DONTNEED, but we do not WILLNEED either. We could potentially make it a ternary operator (false, true, null) where true forces a WILLNEED on flush, so that the name actually makes sense. was (Author: benedict): What makes you say we'll blow away our hot cache on flush? Note that the variable is poorly named, and in fact only provides populateOnFlush => !skipIOCache, i.e. if true we do not explicitly DONTNEED, but we do not WILLNEED. We could potentially make it a ternary operator (false, true, null) where true forces a WILLNEED on flush, so that the name actually makes sense. > Reads have a slow ramp up in speed > ---------------------------------- > > Key: CASSANDRA-6746 > URL: https://issues.apache.org/jira/browse/CASSANDRA-6746 > Project: Cassandra > Issue Type: Bug > Components: Core > Reporter: Ryan McGuire > Assignee: Benedict > Labels: performance > Fix For: 2.1 beta2 > > Attachments: 2.1_vs_2.0_read.png, 6746.txt, > cassandra-2.0-bdplab-trial-fincore.tar.bz2, > cassandra-2.1-bdplab-trial-fincore.tar.bz2 > > > On a physical four node cluister I am doing a big write and then a big read. > The read takes a long time to ramp up to respectable speeds. > !2.1_vs_2.0_read.png! > [See data > here|http://ryanmcguire.info/ds/graph/graph.html?stats=stats.2.1_vs_2.0_vs_1.2.retry1.json&metric=interval_op_rate&operation=stress-read&smoothing=1] -- This message was sent by Atlassian JIRA (v6.2#6252)