|
Problem IT05230
|
Status: Closed |
Inaccurate total cost shown in query plan when intra_parallel is enabled |
| product: |
DB2 FOR LUW / DB2FORLUW / A10 - DB2 |
| Problem description: |
The problem can occur if the optimizer chooses to
intra-parallelize the plan. That is, the "Query Degree" shown in
the query plan is greater than 1.
This can be observed when an intra-parallelized plan is compared
with a serial plan. The total cost of the intra-parallelized
plan is much higher than its corresponding serial plan.
For example:
intra-parallelized plan:
-----------
Total Cost: 1.30441e+21
Query Degree: 24
serial plan:
-----------
Total Cost: 1916.61
Query Degree: 1
The cost difference doesn't affect query performance. |
| Problem Summary: |
****************************************************************
* USERS AFFECTED: *
* Intra-query parallelism *
****************************************************************
* PROBLEM DESCRIPTION: *
* See Error Description *
****************************************************************
* RECOMMENDATION: *
* Upgrade to DB2 Version 10.1 Fix Pack 5. *
**************************************************************** |
| Local Fix: |
|
| Solution |
Fixed in DB2 Version 10.1 Fix Pack 5. |
| Workaround |
not known / see Local fix |
| Timestamps |
Date - problem reported :
Date - problem closed :
Date - last modified :
| 28.10.2014
16.07.2015
16.07.2015 |
| Problem solved at the following versions (IBM BugInfos) |
|
| Problem solved according to the fixlist(s) of the following version(s) |
| 10.1.0.5
|
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