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Jonathan Ellis commented on CASSANDRA-6890: ------------------------------------------- This guy [1] claims that abusing the implementation of FileChannel allows mmap-ing files larger than 2GB, which would allow us to get rid of the SegmentedFile abstraction. [1] http://www.infoq.com/articles/Open-JDK-and-HashMap-Off-Heap > 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_gc.jpg, mmap_jstat.txt, mmap_perf.txt, > nommap_gc.jpg, nommap_jstat.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)