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From Nick Jordan <n...@influen.se>
Subject Re: Decision Forest/Partial Implementation TestForest Error
Date Sat, 08 Sep 2012 17:53:07 GMT
/usr/local/hadoop/hadoop-1.0.3/bin/hadoop jar
/usr/local/mahout/examples/target/mahout-examples-0.8-SNAPSHOT-job.jar
org.apache.mahout.classifier.df.mapreduce.BuildForest
-Dmapred.max.split.size=2167537 -oob -d
/securityWaitTime/wt_top_airports_2007-2012_learn.data -ds
/securityWaitTime/wt_top_airports_2007-2012.info -sl 5 -p -t 100

/usr/local/hadoop/hadoop-1.0.3/bin/hadoop jar
/usr/local/mahout/examples/target/mahout-examples-0.8-SNAPSHOT-job.jar
org.apache.mahout.classifier.df.mapreduce.TestForest -i
/securityWaitTime/wt_top_airports_2007-2012_test.data -ds
/securityWaitTime/wt_top_airports_2007-2012.info -m ob -a -mr -o
predictions

On Sat, Sep 8, 2012 at 5:05 AM, deneche abdelhakim <adeneche@gmail.com> wrote:
> Could you copy/paste the exact commands you used to run the training and
> the testing ?
>
> On Fri, Sep 7, 2012 at 11:10 PM, Nick Jordan <nick@influen.se> wrote:
>
>> Any thoughts here?
>>
>> On Thu, Sep 6, 2012 at 7:00 AM, Nick Jordan <nick@influen.se> wrote:
>> > Same problem with the sequential classifier.  My guess is that this
>> > "corruption" is happening because of that particular setting as it is
>> > the only thing that I'm changing, but I have no idea how to
>> > investigate further.
>> >
>> > Nick
>> >
>> > On Thu, Sep 6, 2012 at 2:22 AM, Abdelhakim Deneche <adeneche@gmail.com>
>> wrote:
>> >> Hi Nick,
>> >>
>> >> This is not a memory problem, the classifier tries to load the trained
>> forest but it's getting some unexpected values. This problem never occured
>> before! Could the forest files be corrupted ?
>> >>
>> >> Try training the forest once again, and this time use the sequential
>> classifier (don't use the -mr parameter) and see if the problem still
>> occurs.
>> >>
>> >>
>> >> On 5 sept. 2012, at 23:00, Nick Jordan <nick@influen.se> wrote:
>> >>
>> >>> Hello All,
>> >>>
>> >>> I'm playing around with decision forests using the partial
>> >>> implementation and my own data set.  I am getting an error with
>> >>> TestForest, but only for certain forests that I'm building with
>> >>> BuildForest.  Using the same descriptor and same build and test data
>> >>> sets I get no error if I set mapred.max.split.size=1890528 which is
>> >>> roughly 1/100th the size of the build data set.  I can build the
>> >>> forest and test the remaining data and get the results with no
>> >>> problem.  When I change the split size to 18905280, everything still
>> >>> appears to work fine when building the forest, but when I then try to
>> >>> test the remaining data I get the error below.
>> >>>
>> >>> I've dug around the code a little, but nothing stood out as to why the
>> >>> array would go out of bounds at that specific value.  One solution is
>> >>> to obviously not create partitions that large, but if it was a problem
>> >>> with me running out of memory I would have expected an out of memory
>> >>> error and not an index past the size the bounds of an array.  I'd
>> >>> obviously prefer larger partitions and thus less of them and can move
>> >>> running this job to something like EMR which should allow me to have
>> >>> more memory, but I want to understand the nature of the error.
>> >>>
>> >>> For what it is worth I'm running this on hadoop-1.0.3 and
>> mahout-0.8-SNAPSHOT
>> >>>
>> >>> Thanks.
>> >>>
>> >>> --
>> >>>
>> >>> 12/09/05 17:52:09 INFO mapred.JobClient: Task Id :
>> >>> attempt_201209031756_0008_m_000000_0, Status : FAILED
>> >>> java.lang.ArrayIndexOutOfBoundsException: 946827879
>> >>>        at org.apache.mahout.classifier.df.node.Node.read(Node.java:58)
>> >>>        at
>> org.apache.mahout.classifier.df.DecisionForest.readFields(DecisionForest.java:197)
>> >>>        at
>> org.apache.mahout.classifier.df.DecisionForest.read(DecisionForest.java:203)
>> >>>        at
>> org.apache.mahout.classifier.df.DecisionForest.load(DecisionForest.java:225)
>> >>>        at
>> org.apache.mahout.classifier.df.mapreduce.Classifier$CMapper.setup(Classifier.java:212)
>> >>>        at org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:142)
>> >>>        at
>> org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:764)
>> >>>        at org.apache.hadoop.mapred.MapTask.run(MapTask.java:370)
>> >>>        at org.apache.hadoop.mapred.Child$4.run(Child.java:255)
>> >>>        at java.security.AccessController.doPrivileged(Native Method)
>> >>>        at javax.security.auth.Subject.doAs(Subject.java:416)
>> >>>        at
>> org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1121)
>> >>>        at org.apache.hadoop.mapred.Child.main(Child.java:249)
>>

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