[jira] [Created] (DRILL-5738) Drill query takes 10+ minutes before start executing, excessive Hive metastore queries

["kevin zou (JIRA)" <ji...@apache.org>]

kevin zou created DRILL-5738:
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             Summary: Drill query takes 10+ minutes before start executing, excessive Hive metastore queries
                 Key: DRILL-5738
                 URL: https://issues.apache.org/jira/browse/DRILL-5738
             Project: Apache Drill
          Issue Type: Bug
          Components: Query Planning & Optimization
    Affects Versions: 1.6.0
         Environment: mapr 5.2
            Reporter: kevin zou
            Priority: Critical


I ve a Drill query on 14 tables in Hive. The query took a few seconds to execute. However, the query would stay in "Starting" state for 10+ minutes before execution. 
 
I set up the log to "Debug" mode to figure out what Drill had been doing during the 10+ minutes, only to find out Drill generated excessive number of meta data queries to hive meta store.  
 
Although each query took a few micro seconds (meta data cached in memory), the number of queries was 3438793.
drillbit.log:2017-06-05 18:50:57,201 [26ca5bda-5e87-475a-cd93-17c6957cc3ee:foreman] DEBUG o.a.d.e.s.hive.HiveMetadataProvider
 - Took 4 µs to get stats from idm_intel_1x.lu_jde_emp_directory
drillbit.log:2017-06-05 18:50:57,201 [26ca5bda-5e87-475a-cd93-17c6957cc3ee:foreman] DEBUG o.a.drill.exec.store.hive.HiveScan
- HiveStats: numRows: 15, sizeInBytes: 15
........



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