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Posted to issues@commons.apache.org by "Adrian Nistor (JIRA)" <ji...@apache.org> on 2012/06/19 18:01:42 UTC

[jira] [Created] (COLLECTIONS-409) ListOrderedSet.addAll() is very slow

Adrian Nistor created COLLECTIONS-409:
-----------------------------------------

             Summary: ListOrderedSet.addAll() is very slow
                 Key: COLLECTIONS-409
                 URL: https://issues.apache.org/jira/browse/COLLECTIONS-409
             Project: Commons Collections
          Issue Type: Bug
    Affects Versions: 3.2.1
         Environment: java 1.6.0_24
Ubuntu 11.10
            Reporter: Adrian Nistor
         Attachments: Test.java, patch.diff

Hi,

I am encountering a performance problem in ListOrderedSet.addAll().
It appears in version 3.2.1 and also in revision 1351465 (18 Jun
2012). I have attached a test that exposes this problem and a
three-line patch that fixes it. On my machine, for this test, the
patch provides a 79X speedup.

To run the test, just do:

$ java Test

The output for the un-patched version is:
Time is 1837

The output for the patched version is:
Time is 23

As the patch shows, the problem is that 
ListOrderedSet.addAll(int index, Collection<? extends E> coll) 
performs:
"setOrder.add(index++, e)" for each element in "coll".  This is very 
expensive, because "setOrder" is an ArrayList, and inserting an
element in the middle of an ArrayList shifts all the elements to the
right.

The patched version avoids this cost by inserting all the elements at
once, thus performing only one insert.

Is this a bug?  If so, can you please confirm that the patch is
correct?

Thanks,

Adrian


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[jira] [Updated] (COLLECTIONS-409) ListOrderedSet.addAll() is very slow

Posted by "Adrian Nistor (JIRA)" <ji...@apache.org>.
     [ https://issues.apache.org/jira/browse/COLLECTIONS-409?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Adrian Nistor updated COLLECTIONS-409:
--------------------------------------

    Attachment: Test.java
                patch.diff
    
> ListOrderedSet.addAll() is very slow
> ------------------------------------
>
>                 Key: COLLECTIONS-409
>                 URL: https://issues.apache.org/jira/browse/COLLECTIONS-409
>             Project: Commons Collections
>          Issue Type: Bug
>    Affects Versions: 3.2.1
>         Environment: java 1.6.0_24
> Ubuntu 11.10
>            Reporter: Adrian Nistor
>         Attachments: Test.java, patch.diff
>
>
> Hi,
> I am encountering a performance problem in ListOrderedSet.addAll().
> It appears in version 3.2.1 and also in revision 1351465 (18 Jun
> 2012). I have attached a test that exposes this problem and a
> three-line patch that fixes it. On my machine, for this test, the
> patch provides a 79X speedup.
> To run the test, just do:
> $ java Test
> The output for the un-patched version is:
> Time is 1837
> The output for the patched version is:
> Time is 23
> As the patch shows, the problem is that 
> ListOrderedSet.addAll(int index, Collection<? extends E> coll) 
> performs:
> "setOrder.add(index++, e)" for each element in "coll".  This is very 
> expensive, because "setOrder" is an ArrayList, and inserting an
> element in the middle of an ArrayList shifts all the elements to the
> right.
> The patched version avoids this cost by inserting all the elements at
> once, thus performing only one insert.
> Is this a bug?  If so, can you please confirm that the patch is
> correct?
> Thanks,
> Adrian

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[jira] [Resolved] (COLLECTIONS-409) ListOrderedSet.addAll() is very slow

Posted by "Thomas Neidhart (JIRA)" <ji...@apache.org>.
     [ https://issues.apache.org/jira/browse/COLLECTIONS-409?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Thomas Neidhart resolved COLLECTIONS-409.
-----------------------------------------

       Resolution: Fixed
    Fix Version/s: 4.0

Applied the patch in r1351821.

Thanks for reporting!
                
> ListOrderedSet.addAll() is very slow
> ------------------------------------
>
>                 Key: COLLECTIONS-409
>                 URL: https://issues.apache.org/jira/browse/COLLECTIONS-409
>             Project: Commons Collections
>          Issue Type: Bug
>    Affects Versions: 3.2.1
>         Environment: java 1.6.0_24
> Ubuntu 11.10
>            Reporter: Adrian Nistor
>             Fix For: 4.0
>
>         Attachments: Test.java, patch.diff
>
>
> Hi,
> I am encountering a performance problem in ListOrderedSet.addAll().
> It appears in version 3.2.1 and also in revision 1351465 (18 Jun
> 2012). I have attached a test that exposes this problem and a
> three-line patch that fixes it. On my machine, for this test, the
> patch provides a 79X speedup.
> To run the test, just do:
> $ java Test
> The output for the un-patched version is:
> Time is 1837
> The output for the patched version is:
> Time is 23
> As the patch shows, the problem is that 
> ListOrderedSet.addAll(int index, Collection<? extends E> coll) 
> performs:
> "setOrder.add(index++, e)" for each element in "coll".  This is very 
> expensive, because "setOrder" is an ArrayList, and inserting an
> element in the middle of an ArrayList shifts all the elements to the
> right.
> The patched version avoids this cost by inserting all the elements at
> once, thus performing only one insert.
> Is this a bug?  If so, can you please confirm that the patch is
> correct?
> Thanks,
> Adrian

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[jira] [Commented] (COLLECTIONS-409) ListOrderedSet.addAll() is very slow

Posted by "Hudson (JIRA)" <ji...@apache.org>.
    [ https://issues.apache.org/jira/browse/COLLECTIONS-409?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13397032#comment-13397032 ] 

Hudson commented on COLLECTIONS-409:
------------------------------------

Integrated in commons-collections #23 (See [https://builds.apache.org/job/commons-collections/23/])
    [COLLECTIONS-409] Improve performance of ListOrderedSet#addAll, add missing javadoc. Thanks to Adrian Nistor for reporting and providing a patch. (Revision 1351821)

     Result = SUCCESS
tn : http://svn.apache.org/viewvc/?view=rev&rev=1351821
Files : 
* /commons/proper/collections/trunk/src/main/java/org/apache/commons/collections/set/ListOrderedSet.java

                
> ListOrderedSet.addAll() is very slow
> ------------------------------------
>
>                 Key: COLLECTIONS-409
>                 URL: https://issues.apache.org/jira/browse/COLLECTIONS-409
>             Project: Commons Collections
>          Issue Type: Bug
>    Affects Versions: 3.2.1
>         Environment: java 1.6.0_24
> Ubuntu 11.10
>            Reporter: Adrian Nistor
>             Fix For: 4.0
>
>         Attachments: Test.java, patch.diff
>
>
> Hi,
> I am encountering a performance problem in ListOrderedSet.addAll().
> It appears in version 3.2.1 and also in revision 1351465 (18 Jun
> 2012). I have attached a test that exposes this problem and a
> three-line patch that fixes it. On my machine, for this test, the
> patch provides a 79X speedup.
> To run the test, just do:
> $ java Test
> The output for the un-patched version is:
> Time is 1837
> The output for the patched version is:
> Time is 23
> As the patch shows, the problem is that 
> ListOrderedSet.addAll(int index, Collection<? extends E> coll) 
> performs:
> "setOrder.add(index++, e)" for each element in "coll".  This is very 
> expensive, because "setOrder" is an ArrayList, and inserting an
> element in the middle of an ArrayList shifts all the elements to the
> right.
> The patched version avoids this cost by inserting all the elements at
> once, thus performing only one insert.
> Is this a bug?  If so, can you please confirm that the patch is
> correct?
> Thanks,
> Adrian

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