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Jonathan Ellis commented on CASSANDRA-4338: ------------------------------------------- I'd vote for: - test with LCS, with/without compression (maybe even reduce sstable size to 1MB to really stress sstable creation) - enable gc logging, count promotion failures so we have quantitative data (if we see zero both ways, we may need a more complex test) - if instead we see nonzero promotion failures both ways, at about the same rate, we might need to look at using our "cleaner" hack to free the direct buffers, or use a buffer based on FreeableMemory, to avoid the phantomreference crap that DirectBuffer normally inflicts on GC > Experiment with direct buffer in SequentialWriter > ------------------------------------------------- > > Key: CASSANDRA-4338 > URL: https://issues.apache.org/jira/browse/CASSANDRA-4338 > Project: Cassandra > Issue Type: Improvement > Components: Core > Reporter: Jonathan Ellis > Assignee: Yuki Morishita > Priority: Minor > Fix For: 1.2 > > Attachments: gc-4338-patched.png, gc-trunk.png > > > Using a direct buffer instead of a heap-based byte[] should let us avoid a > copy into native memory when we flush the buffer. -- 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