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liyang commented on KYLIN-2926: ------------------------------- As mentioned in KYLIN-2944, I do have concern here. The sharing of object is for performance sake, the same reason as Mapper and Reducer reusing objects in their interfaces. I'm doing a quick benchmark to see the performance difference. > DumpMerger return incorrect results > ----------------------------------- > > Key: KYLIN-2926 > URL: https://issues.apache.org/jira/browse/KYLIN-2926 > Project: Kylin > Issue Type: Bug > Affects Versions: v2.0.0 > Reporter: fengYu > Assignee: fengYu > Attachments: > 0001-KYLIN-2926-DumpMerger-return-incorrect-results-creat.patch > > > I our scenario, a cube query will get wrong result once coprocessor need to > spill to disk, Our version is 2.0.0 and I find the root cause is that in > DumpMerger.enqueueFromDump > because in DataTypeSerializer kylin use a ThreadLocal variable ‘current’, It > leading to different elements in dumpCurrentValues share the same object, so > next fill up measure values will change the existing values. > the incorrect measures is HLLC and raw, which use current variable in > deserialize. -- This message was sent by Atlassian JIRA (v6.4.14#64029)