[
https://issues.apache.org/jira/browse/TAJO-1716?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14644252#comment-14644252
]
ASF GitHub Bot commented on TAJO-1716:
--------------------------------------
GitHub user jihoonson opened a pull request:
https://github.com/apache/tajo/pull/659
TAJO-1716: Repartitioner.makeEvenDistributedFetchImpl() does not distribute
fetches evenly
Here is the evaluation result.
* # of samples: 1000
* # of fetches: 2000
### Before patch
```
# of partitions: 10
std dev: 7239.203108077597
# of partitions: 20
std dev: 2507.946123823235
# of partitions: 30
std dev: 1337.669359578645
# of partitions: 40
std dev: 847.1299428068963
# of partitions: 50
std dev: 590.6100520648041
# of partitions: 60
std dev: 441.75456483838553
# of partitions: 70
std dev: 340.5741442844647
# of partitions: 80
std dev: 270.92110936581224
# of partitions: 90
std dev: 221.5819175222533
# of partitions: 100
std dev: 184.4234215060522
```
### After patch
```
# of partitions: 10
13.61763562654033
# of partitions: 20
21.6693331706813
# of partitions: 30
15.134361197689614
# of partitions: 40
13.04185569631777
# of partitions: 50
14.063911262269487
# of partitions: 60
12.51514637879624
# of partitions: 70
12.309312883565598
# of partitions: 80
29.554991118293103
# of partitions: 90
37.39714123885218
# of partitions: 100
11.820253804288662
```
You can merge this pull request into a Git repository by running:
$ git pull https://github.com/jihoonson/tajo-2 TAJO-1716
Alternatively you can review and apply these changes as the patch at:
https://github.com/apache/tajo/pull/659.patch
To close this pull request, make a commit to your master/trunk branch
with (at least) the following in the commit message:
This closes #659
----
commit f26cfd789fe0a8ce464049aae3b37278c6d72795
Author: Jihoon Son <[email protected]>
Date: 2015-07-28T11:23:39Z
TAJO-1716
----
> Repartitioner.makeEvenDistributedFetchImpl() does not distribute fetches
> evenly
> -------------------------------------------------------------------------------
>
> Key: TAJO-1716
> URL: https://issues.apache.org/jira/browse/TAJO-1716
> Project: Tajo
> Issue Type: Bug
> Components: distributed query plan
> Reporter: Jihoon Son
> Assignee: Jihoon Son
> Fix For: 0.11.0
>
>
> Repartitioner.makeEvenDistributedFetchImpl() is to be designed to create
> partitions with balancing the fetch size of each partition. Currently, it
> does not create partitions evenly due to a trivial bug.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
