[HIVE-7669] parallel order by clause on a string column fails with IOException: Split points are out of order

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.12.0
• Fix Version/s: 0.14.0
• Component/s: HiveServer2, Query Processor, SQL
• Labels: orderby

Environment

Hive 0.12.0-cdh5.0.0
OS: Redhat linux

Release Note

Background: HIVE-1402 added parallelism (multiple reducers) to an order-by query, enabled by "hive.optimize.sampling.orderby". As order-by requires total order, partitioning data among reducers uses a range-partition, and thus sampling is needed to give us the values for the ranges of each reducer (eg, 1-100, 100-200, etc).

HIVE-7669 fixes the algorithm to generate a better range-partition split when the sample data lacks enough unique values.

• Tags: Parallel Order by on String column
• Assignee: Navis Ryu
• Reporter: Vishal Kamath
• Created: 09/Aug/14 01:07
• Updated: 13/Nov/14 19:41
• Resolved: 01/Sep/14 05:29

Description

The source table has 600 Million rows and it has a String column "l_shipinstruct" which has 4 unique values. (Ie. these 4 values are repeated across the 600 million rows)

We are sorting it based on this string column "l_shipinstruct" as shown in the below HiveQL with the following parameters.

set hive.optimize.sampling.orderby=true;
set hive.optimize.sampling.orderby.number=10000000;
set hive.optimize.sampling.orderby.percent=0.1f;

insert overwrite table lineitem_temp_report 
select 
  l_orderkey, l_partkey, l_suppkey, l_linenumber, l_quantity, l_extendedprice, l_discount, l_tax, l_returnflag, l_linestatus, l_shipdate, l_commitdate, l_receiptdate, l_shipinstruct, l_shipmode, l_comment
from 
  lineitem
order by l_shipinstruct;

Stack Trace
Diagnostic Messages for this Task:

Error: java.lang.RuntimeException: Error in configuring object
        at org.apache.hadoop.util.ReflectionUtils.setJobConf(ReflectionUtils.java:109)
        at org.apache.hadoop.util.ReflectionUtils.setConf(ReflectionUtils.java:75)
        at org.apache.hadoop.util.ReflectionUtils.newInstance(ReflectionUtils.java:133)
        at org.apache.hadoop.mapred.MapTask$OldOutputCollector.<init>(MapTask.java:569)
        at org.apache.hadoop.mapred.MapTask.runOldMapper(MapTask.java:430)
        at org.apache.hadoop.mapred.MapTask.run(MapTask.java:342)
        at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:168)
        at java.security.AccessController.doPrivileged(Native Method)
        at javax.security.auth.Subject.doAs(Subject.java:415)
        at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1548)
        at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:163)
Caused by: java.lang.reflect.InvocationTargetException
        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:601)
        at org.apache.hadoop.util.ReflectionUtils.setJobConf(ReflectionUtils.java:106)
        ... 10 more
Caused by: java.lang.IllegalArgumentException: Can't read partitions file
        at org.apache.hadoop.mapreduce.lib.partition.TotalOrderPartitioner.setConf(TotalOrderPartitioner.java:116)
        at org.apache.hadoop.mapred.lib.TotalOrderPartitioner.configure(TotalOrderPartitioner.java:42)
        at org.apache.hadoop.hive.ql.exec.HiveTotalOrderPartitioner.configure(HiveTotalOrderPartitioner.java:37)
        ... 15 more
Caused by: java.io.IOException: Split points are out of order
        at org.apache.hadoop.mapreduce.lib.partition.TotalOrderPartitioner.setConf(TotalOrderPartitioner.java:96)
        ... 17 more

Issue Links

• relates to: HIVE-1402 Add parallel ORDER BY to Hive
• links to: review board