[ https://issues.apache.org/jira/browse/HBASE-3455?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Todd Lipcon updated HBASE-3455: ------------------------------- Attachment: mslab-6.txt New rev takes Stack's suggestions: - better comment on the upsert code - actually enabled the test in memstore, since fixing the upsert code lets that test pass - this way if we accidentally start using MSLAB for upsert it'll fail. - MemStoreLAB now returns null for large allocs, and MemStore doesnt clone > Heap fragmentation in region server > ----------------------------------- > > Key: HBASE-3455 > URL: https://issues.apache.org/jira/browse/HBASE-3455 > Project: HBase > Issue Type: Brainstorming > Components: performance, regionserver > Affects Versions: 0.90.1 > Reporter: Todd Lipcon > Assignee: Todd Lipcon > Priority: Critical > Fix For: 0.90.1 > > Attachments: HBasefragmentation.pdf, collapse-arrays.patch, > icv-frag.png, mslab-1.txt, mslab-2.txt, mslab-3.txt, mslab-4.txt, > mslab-5.txt, mslab-6.txt, parse-fls-statistics.py, with-kvallocs.png > > > Stop-the-world GC pauses have long been a problem in HBase. "Concurrent mode > failures" can usually be tuned around by setting the initiating occupancy > fraction low, but eventually the heap becomes fragmented and a promotion > failure occurs. > This JIRA is to do research/experiments about the heap fragmentation issue > and possible solutions. -- This message is automatically generated by JIRA. - For more information on JIRA, see: http://www.atlassian.com/software/jira