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Pavel Yaskevich commented on CASSANDRA-3623: -------------------------------------------- Can you please compare your version with trunk without crc32 because it doesn't seem to be fare match, would be nice to see the same statistics about hot methods and response time. The thing that I hate about MappedByteBuffer is if you duplicate it like you do in reBuffer() - will make unmap impossible until the every last duplicate is GC'ed, this implies that we won't be able to release old SSTables... > use MMapedBuffer in CompressedSegmentedFile.getSegment > ------------------------------------------------------ > > Key: CASSANDRA-3623 > URL: https://issues.apache.org/jira/browse/CASSANDRA-3623 > Project: Cassandra > Issue Type: Improvement > Components: Core > Affects Versions: 1.1 > Reporter: Vijay > Assignee: Vijay > Labels: compression > Fix For: 1.1 > > Attachments: 0001-MMaped-Compression-segmented-file-v2.patch, > 0001-MMaped-Compression-segmented-file.patch, > 0002-tests-for-MMaped-Compression-segmented-file-v2.patch > > > CompressedSegmentedFile.getSegment seem to open a new file and doesnt seem to > use the MMap and hence a higher CPU on the nodes and higher latencies on > reads. > This ticket is to implement the TODO mentioned in CompressedRandomAccessReader > // TODO refactor this to separate concept of "buffer to avoid lots of read() > syscalls" and "compression buffer" > but i think a separate class for the Buffer will be better. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa For more information on JIRA, see: http://www.atlassian.com/software/jira