[IMPALA-4511] Regression : Reported Fragment total time is incorrect

• Type: Bug
• Status: Resolved
• Priority: Blocker
• Resolution: Fixed
• Affects Version/s: Impala 2.8.0
• Fix Version/s: Impala 2.8.0
• Component/s: Backend
• Labels: profile supportability
• Target Version: Impala 2.8.0
• Assignee: Henry Robinson
• Reporter: Mostafa Mokhtar
• Created: 18/Nov/16 22:20
• Updated: 07/Dec/16 02:49
• Resolved: 07/Dec/16 02:49

Description

A recent change seems to have broken the fragment reported timings

    Averaged Fragment F00:(Total: 43.874ms, non-child: 0.000ns, % non-child: 0.00%)
      split sizes:  min: 7.88 GB, max: 7.95 GB, avg: 7.92 GB, stddev: 21.60 MB
      completion times: min:19s509ms  max:19s883ms  mean: 19s720ms  stddev:112.439ms
      execution rates: min:407.03 MB/sec  max:416.52 MB/sec  mean:411.07 MB/sec  stddev:2.89 MB/sec
      num instances: 15
       - AverageThreadTokens: 11.32 
       - BloomFilterBytes: 17.00 MB (17825792)
       - PeakMemoryUsage: 123.02 MB (128992933)
       - PerHostPeakMemUsage: 844.39 MB (885405464)
       - RowsProduced: 6.75M (6745672)
       - TotalCpuTime: 3m25s
       - TotalNetworkReceiveTime: 0.000ns
       - TotalNetworkSendTime: 17s164ms
       - TotalStorageWaitTime: 394.254ms
      Fragment Instance Lifecycle Timings:
         - ExecTime: 19s670ms
           - ExecTreeExecTime: 1s034ms
         - OpenTime: 17.251ms
           - ExecTreeOpenTime: 142.269us
         - PrepareTime: 26.600ms
           - ExecTreePrepareTime: 20.760ms

Before the regression

    Averaged Fragment F00:(Total: 29s527ms, non-child: 3s362ms, % non-child: 11.39%)
      split sizes:  min: 11.46 GB, max: 12.01 GB, avg: 11.77 GB, stddev: 124.72 MB
      completion times: min:17s281ms  max:46s307ms  mean: 30s414ms  stddev:7s903ms
      execution rates: min:255.29 MB/sec  max:699.00 MB/sec  mean:426.25 MB/sec  stddev:121.13 MB/sec
      num instances: 32
       - AverageThreadTokens: 3.86 
       - BloomFilterBytes: 27.00 MB (28311552)
       - PeakMemoryUsage: 219.11 MB (229755142)
       - PerHostPeakMemUsage: 1.48 GB (1588976755)
       - PrepareTime: 171.122ms
       - RowsProduced: 7.59M (7590805)
       - TotalCpuTime: 1m42s
       - TotalNetworkReceiveTime: 16s432ms
       - TotalNetworkSendTime: 236.902ms
       - TotalStorageWaitTime: 499.184ms