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Joshua McKenzie commented on CASSANDRA-6890: -------------------------------------------- Initial testing indicates a performance regression. Just commenting out / changing the type of SegmentedFile we're using is showing the #'s listed in my previous comment. I'll be working on getting clarity as to why this is taking place before moving forward on actually submitting a patch to remove the functionality. > Remove mmap'ed i/o from read path > --------------------------------- > > Key: CASSANDRA-6890 > URL: https://issues.apache.org/jira/browse/CASSANDRA-6890 > Project: Cassandra > Issue Type: Improvement > Reporter: Joshua McKenzie > Assignee: Joshua McKenzie > Priority: Minor > Fix For: 3.0 > > Attachments: mmap_perf.txt > > > Since we actively unmap unreferenced SSTR's and also copy data out of those > readers on the read path, the current memory mapped i/o is a lot of > complexity for very little payoff. Clean out the mmapp'ed i/o on the read > path. -- This message was sent by Atlassian JIRA (v6.2#6252)