[
https://issues.apache.org/jira/browse/HIVE-7397?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14059667#comment-14059667
]
Gopal V commented on HIVE-7397:
-------------------------------
Candidate queries for my test were
{code}
select * from store_sales where year(ss_sold_date)=2002 and
month(ss_sold_date)=12 limit 200;
select ss_item_sk from store_sales where ss_sold_date = '2002-01-01';
select ss_item_sk from store_sales where ss_sold_date = '2002-01-01' and
ss_quantity < 2;
{code}
The current exit criteria for this test is that the first 2 should always hit
the "more" criteria irrespective of data-sizes.
The latter should only go there if the whole data-set for 2002-01-01 is < 1Gb.
> Set the default threshold for fetch task conversion to 1Gb
> ----------------------------------------------------------
>
> Key: HIVE-7397
> URL: https://issues.apache.org/jira/browse/HIVE-7397
> Project: Hive
> Issue Type: Bug
> Affects Versions: 0.14.0, 0.13.1
> Reporter: Gopal V
> Assignee: Gopal V
> Labels: Performance
> Fix For: 0.14.0
>
>
> Currently, modifying the value of hive.fetch.task.conversion to "more"
> results in a dangerous setting where small scale queries function, but large
> scale queries crash.
> This occurs because the default threshold of -1 means apply this optimization
> for a petabyte table.
> I am testing a variety of queries with the setting "more" (to make it the
> default option as suggested by HIVE-887) change the default threshold for
> this feature to a reasonable 1Gb.
--
This message was sent by Atlassian JIRA
(v6.2#6252)
