[KYLIN-2926] DumpMerger return incorrect results

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: v2.0.0
• Fix Version/s: v2.2.0
• Component/s: Query Engine
• Assignee: fengYu
• Reporter: fengYu
• Created: 11/Oct/17 06:59
• Updated: 05/Nov/17 09:32
• Resolved: 05/Nov/17 09:30

Description

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.

Issue Links

• relates to: KYLIN-2944 HLLCSerializer, RawSerializer, PercentileSerializer returns shared object in serialize()