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https://issues.apache.org/jira/browse/HIVE-2372?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14027993#comment-14027993
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Sergey Tryuber commented on HIVE-2372:
--------------------------------------
Hi Ryan,
Yes, your issue is very related. Hive passes properties to TRANSFORM script via
environment variables. In the scope of this ticket I've shortened only
environment variable which stores information about partitions.
In case of user-defined variables (via SET statement), I'm not even sure that
approach to shorten them is correct. May be it would be better just to fail
with error before map-reduce job execution and ask user to unset the variable
(as you did). But it is quite hard to judge what is length limitation, because
it depends on OS (even in my patch, as I remember, I hardcoded the length and
now it seems to be not the best choice). As an alternative, Hive can print a
warning, but continue the execution.
Anyway, this issue had been closed so much time ago (and applied patch really
solves the problem in issue description) that I think it would be better to
create a new one and lead all the discussion there. Don't you mind to do it?
> java.io.IOException: error=7, Argument list too long
> ----------------------------------------------------
>
> Key: HIVE-2372
> URL: https://issues.apache.org/jira/browse/HIVE-2372
> Project: Hive
> Issue Type: Bug
> Components: Query Processor
> Affects Versions: 0.12.0
> Reporter: Sergey Tryuber
> Priority: Critical
> Fix For: 0.10.0
>
> Attachments: HIVE-2372.1.patch.txt, HIVE-2372.2.patch.txt
>
>
> I execute a huge query on a table with a lot of 2-level partitions. There is
> a perl reducer in my query. Maps worked ok, but every reducer fails with the
> following exception:
> 2011-08-11 04:58:29,865 INFO org.apache.hadoop.hive.ql.exec.ScriptOperator:
> Executing [/usr/bin/perl, <reducer.pl>, <my_argument>]
> 2011-08-11 04:58:29,866 INFO org.apache.hadoop.hive.ql.exec.ScriptOperator:
> tablename=null
> 2011-08-11 04:58:29,866 INFO org.apache.hadoop.hive.ql.exec.ScriptOperator:
> partname=null
> 2011-08-11 04:58:29,866 INFO org.apache.hadoop.hive.ql.exec.ScriptOperator:
> alias=null
> 2011-08-11 04:58:29,935 FATAL ExecReducer:
> org.apache.hadoop.hive.ql.metadata.HiveException: Hive Runtime Error while
> processing row (tag=0)
> {"key":{"reducesinkkey0":129390185139228,"reducesinkkey1":"00008AF10000000063CA6F"},"value":{"_col0":"00008AF10000000063CA6F","_col1":"2011-07-27
>
> 22:48:52","_col2":129390185139228,"_col3":2006,"_col4":4100,"_col5":"10017388=6","_col6":1063,"_col7":"NULL","_col8":"address.com","_col9":"NULL","_col10":"NULL"},"alias":0}
> at
> org.apache.hadoop.hive.ql.exec.ExecReducer.reduce(ExecReducer.java:256)
> at
> org.apache.hadoop.mapred.ReduceTask.runOldReducer(ReduceTask.java:468)
> at org.apache.hadoop.mapred.ReduceTask.run(ReduceTask.java:416)
> at org.apache.hadoop.mapred.Child$4.run(Child.java:268)
> at java.security.AccessController.doPrivileged(Native Method)
> at javax.security.auth.Subject.doAs(Subject.java:396)
> at
> org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1115)
> at org.apache.hadoop.mapred.Child.main(Child.java:262)
> Caused by: org.apache.hadoop.hive.ql.metadata.HiveException: Cannot
> initialize ScriptOperator
> at
> org.apache.hadoop.hive.ql.exec.ScriptOperator.processOp(ScriptOperator.java:320)
> at org.apache.hadoop.hive.ql.exec.Operator.process(Operator.java:471)
> at org.apache.hadoop.hive.ql.exec.Operator.forward(Operator.java:744)
> at
> org.apache.hadoop.hive.ql.exec.SelectOperator.processOp(SelectOperator.java:84)
> at org.apache.hadoop.hive.ql.exec.Operator.process(Operator.java:471)
> at org.apache.hadoop.hive.ql.exec.Operator.forward(Operator.java:744)
> at
> org.apache.hadoop.hive.ql.exec.ExtractOperator.processOp(ExtractOperator.java:45)
> at org.apache.hadoop.hive.ql.exec.Operator.process(Operator.java:471)
> at
> org.apache.hadoop.hive.ql.exec.ExecReducer.reduce(ExecReducer.java:247)
> ... 7 more
> Caused by: java.io.IOException: Cannot run program "/usr/bin/perl":
> java.io.IOException: error=7, Argument list too long
> at java.lang.ProcessBuilder.start(ProcessBuilder.java:460)
> at
> org.apache.hadoop.hive.ql.exec.ScriptOperator.processOp(ScriptOperator.java:279)
> ... 15 more
> Caused by: java.io.IOException: java.io.IOException: error=7, Argument list
> too long
> at java.lang.UNIXProcess.<init>(UNIXProcess.java:148)
> at java.lang.ProcessImpl.start(ProcessImpl.java:65)
> at java.lang.ProcessBuilder.start(ProcessBuilder.java:453)
> ... 16 more
> It seems to me, I found the cause. ScriptOperator.java puts a lot of configs
> as environment variables to the child reduce process. One of variables is
> mapred.input.dir, which in my case more than 150KB. There are a huge amount
> of input directories in this variable. In short, the problem is that Linux
> (up to 2.6.23 kernel version) limits summary size of environment variables
> for child processes to 132KB. This problem could be solved by upgrading the
> kernel. But strings limitations still be 132KB per string in environment
> variable. So such huge variable doesn't work even on my home computer
> (2.6.32). You can read more information on
> (http://www.kernel.org/doc/man-pages/online/pages/man2/execve.2.html).
> For now all our work has been stopped because of this problem and I can't
> find the solution. The only solution, which seems to me more reasonable is to
> get rid of this variable in reducers.
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