Csaba Ringhofer has posted comments on this change. ( 
http://gerrit.cloudera.org:8080/10628 )

Change subject: IMPALA-7115: set a default THREAD_RESERVATION_LIMIT value
......................................................................


Patch Set 1:

(1 comment)

http://gerrit.cloudera.org:8080/#/c/10628/1/testdata/workloads/functional-query/queries/QueryTest/thread-limits.test
File testdata/workloads/functional-query/queries/QueryTest/thread-limits.test:

http://gerrit.cloudera.org:8080/#/c/10628/1/testdata/workloads/functional-query/queries/QueryTest/thread-limits.test@109
PS1, Line 109: SELECT count(*) from functional.alltypes
When I am trying to create a plan with crazy amount of nodes, I use WITH + 
UNION to get exponential growth. The following query should lead to at least 
1000 fragments:

explain with
 c1 as (select count(*) from functional.alltypes),
 c2 as (select * from c1 union select * from c1),
 c4 as (select * from c2 union select * from c2),
 c8 as (select * from c4 union select * from c4),
 c16 as (select * from c8 union select * from c8),
 c32 as (select * from c16 union select * from c16),
 c64 as (select * from c32 union select * from c32),
 c128 as (select * from c64 union select * from c64),
 c256 as (select * from c128 union select * from c128),
 c512 as (select * from c256 union select * from c256)
select * from c512 union select * from c512;

I think that the resulting plan would not be the same as with the flat list of 
unions, but it would do the job while the test would be much more compact.



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Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-MessageType: comment
Gerrit-Change-Id: I31d3fa3f6305c360922649dba53a9026c9563384
Gerrit-Change-Number: 10628
Gerrit-PatchSet: 1
Gerrit-Owner: Tim Armstrong <[email protected]>
Gerrit-Reviewer: Csaba Ringhofer <[email protected]>
Gerrit-Reviewer: Dan Hecht <[email protected]>
Gerrit-Comment-Date: Thu, 14 Jun 2018 14:42:02 +0000
Gerrit-HasComments: Yes

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