|
Problem IT33973
|
Status: Closed |
APPLICATION IN UOW EXECUTING USING HASH JOINS MAY HANG AND COULDNOT BE FORCED OFF
|
| product: |
DB2 FOR LUW / DB2FORLUW / B10 - DB2 |
| Problem description: |
The conditions which cause this issue are as follows:
1. SMP environment
2. Automatic setting of SORTHEAP
3. Query using HSJOIN
4. Extremely memory constrained environment
Application may stuck in
'Application status' = UOW Executing
Trying to force this application does not work. It keeps
running.
The stack of this coordinator agent may show:
sqlkdInterrupt
sqlriecc
sqlrr_process_close_request
sqlrr_fetch_error
sqlrr_open
sqljs_ddm_opnqry
sqljsParseRdbAccessed
...
All its smp subagents are in sqloXlatchConflict and at least one
will be in sqlri_hsjnFlushBlocks:
sqloXlatchConflict
sqlri_hsjnFlushBlocks
sqlri_hsjnPartitionFull
sqlri_hsjnProcessBuildTuple
sqlrihsjnBuildPD
sqldDataFetch
...
Other stack should have sqlri_hsjnHeapReduction and
sqlri_hsjnFlushBlocks like so:
sqloXlatchConflict
sqlri_hsjnFlushBlocks
sqlri_hsjnHeapReduction
sqlri_hsjnGetTupleBlock
sqlri_hsjnPartitionFull
sqlri_hsjnProcessBuildTuple
sqlrihsjnBuildPD
db2diag.log may be flushed with messages from STMM trying to
reduce SORTHEAP memory.
This fix will cause error SQL0955N to be returned when this
happens and force off the application and not cause any hangs. |
| Problem Summary: |
****************************************************************
* USERS AFFECTED: *
* all *
****************************************************************
* PROBLEM DESCRIPTION: *
* See Error Description *
****************************************************************
* RECOMMENDATION: *
* Upgrade to Db2 11.1.4.6 or higher *
**************************************************************** |
| Local Fix: |
To get out of the hang situation, kill the process executing the
application
and
to prevent it:
Apply degree=1 on per query basis.
/* */
for this query. |
| Solution |
|
| Workaround |
not known / see Local fix |
| Timestamps |
Date - problem reported :
Date - problem closed :
Date - last modified :
| 21.08.2020
31.03.2021
31.03.2021 |
| Problem solved at the following versions (IBM BugInfos) |
|
| Problem solved according to the fixlist(s) of the following version(s) |
