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Jonathan Ellis commented on CASSANDRA-2459: ------------------------------------------- (a) we still need to avoid pushing hot rows out w/ our sequential scan; it seems to me that using the same source as the read stage makes this harder, not easier. > move SSTableScanner to use SSTableReader.dfile instead of BRAF > -------------------------------------------------------------- > > Key: CASSANDRA-2459 > URL: https://issues.apache.org/jira/browse/CASSANDRA-2459 > Project: Cassandra > Issue Type: Improvement > Components: Core > Reporter: Pavel Yaskevich > Assignee: Pavel Yaskevich > Fix For: 1.0 > > > That can give us the following benefits: > a). don't need to skip a cache because we will be operating on memory mappings > b). better performance (not copying data between kernel and user buffers as > effect gained from using memory mapped segments, avoiding time operating on > the kernel mode (+ time for switching context and read-ahead pressure) which > BRAF involves) > c). less impact on the live-reads > d). less garbage will be created > e). less file descriptors opened -- This message is automatically generated by JIRA. For more information on JIRA, see: http://www.atlassian.com/software/jira