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Posted to dev@hive.apache.org by "Rajesh Balamohan (JIRA)" <ji...@apache.org> on 2016/10/10 11:08:20 UTC

[jira] [Created] (HIVE-14920) S3: Optimize SimpleFetchOptimizer::checkThreshold()

Rajesh Balamohan created HIVE-14920:
---------------------------------------

             Summary: S3: Optimize SimpleFetchOptimizer::checkThreshold()
                 Key: HIVE-14920
                 URL: https://issues.apache.org/jira/browse/HIVE-14920
             Project: Hive
          Issue Type: Improvement
            Reporter: Rajesh Balamohan
            Assignee: Rajesh Balamohan
            Priority: Minor


Query: Simple query like the following takes lot longer time in query compilation phase (~330 seconds for 200 GB dataset with tpc-ds)
{noformat}
select ws_item_sk from web_sales where ws_item_sk > 10 limit 10;
{noformat}

This enables {{SimpleFetchOptimizer}} which internally tries to figure out if the size of the data is within the threshold defined in {{hive.fetch.task.conversion.threshold}} ~1GB.

This turns out to be super expensive when the dataset is partitioned. E.g stacktrace is given below. Note that this happens in client side and tries to get the length for 1800+ partitions before proceeding to next rule.

{noformat}
        at org.apache.hadoop.fs.FileSystem.getContentSummary(FileSystem.java:1486)
        at org.apache.hadoop.hive.ql.optimizer.SimpleFetchOptimizer$FetchData.getFileLength(SimpleFetchOptimizer.java:466)
        at org.apache.hadoop.hive.ql.optimizer.SimpleFetchOptimizer$FetchData.calculateLength(SimpleFetchOptimizer.java:451)
        at org.apache.hadoop.hive.ql.optimizer.SimpleFetchOptimizer$FetchData.getInputLength(SimpleFetchOptimizer.java:423)
        at org.apache.hadoop.hive.ql.optimizer.SimpleFetchOptimizer$FetchData.access$300(SimpleFetchOptimizer.java:323)
        at org.apache.hadoop.hive.ql.optimizer.SimpleFetchOptimizer.checkThreshold(SimpleFetchOptimizer.java:168)
        at org.apache.hadoop.hive.ql.optimizer.SimpleFetchOptimizer.optimize(SimpleFetchOptimizer.java:133)
        at org.apache.hadoop.hive.ql.optimizer.SimpleFetchOptimizer.transform(SimpleFetchOptimizer.java:105)
        at org.apache.hadoop.hive.ql.optimizer.Optimizer.optimize(Optimizer.java:207)
        at org.apache.hadoop.hive.ql.parse.SemanticAnalyzer.analyzeInternal(SemanticAnalyzer.java:10466)
        at org.apache.hadoop.hive.ql.parse.CalcitePlanner.analyzeInternal(CalcitePlanner.java:216)
        at org.apache.hadoop.hive.ql.parse.BaseSemanticAnalyzer.analyze(BaseSemanticAnalyzer.java:230)
        at org.apache.hadoop.hive.ql.parse.ExplainSemanticAnalyzer.analyzeInternal(ExplainSemanticAnalyzer.java:74)
        at org.apache.hadoop.hive.ql.parse.BaseSemanticAnalyzer.analyze(BaseSemanticAnalyzer.java:230)
        at org.apache.hadoop.hive.ql.Driver.compile(Driver.java:464)
        at org.apache.hadoop.hive.ql.Driver.compile(Driver.java:320)
        at org.apache.hadoop.hive.ql.Driver.compileInternal(Driver.java:1219)
        at org.apache.hadoop.hive.ql.Driver.runInternal(Driver.java:1260)
        at org.apache.hadoop.hive.ql.Driver.run(Driver.java:1156)
        at org.apache.hadoop.hive.ql.Driver.run(Driver.java:1146)
        at org.apache.hadoop.hive.cli.CliDriver.processLocalCmd(CliDriver.java:217)
        at org.apache.hadoop.hive.cli.CliDriver.processCmd(CliDriver.java:169)
        at org.apache.hadoop.hive.cli.CliDriver.processLine(CliDriver.java:380)
        at org.apache.hadoop.hive.cli.CliDriver.executeDriver(CliDriver.java:740)
        at org.apache.hadoop.hive.cli.CliDriver.run(CliDriver.java:685)
        at org.apache.hadoop.hive.cli.CliDriver.main(CliDriver.java:625)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:606)
        at org.apache.hadoop.util.RunJar.run(RunJar.java:233)
        at org.apache.hadoop.util.RunJar.main(RunJar.java:148)
{noformat}




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