A fix is available
APAR status
Closed as program error.
Error description
See PI78282 for DB2 12 for z/OS. DB2 REQUESTER APPLICATION WHICH USES DRDACDF BOUND PACKAGES AND REFERENCES DB2 REMOTE LOCATIONS MAY TERMINATE WITHOUT PROPERLY TERMINATING CONNECTIONS TO THE REMOTE LOCATIONS. ORPHAN CONNECTION/THREADS AT THOSE DB2 REMOTE LOCATIONS WILL REMAIN ACTIVE HOLDING LOCKS, THREAD SLOTS, ETC., WHICH WOULD THEN LEAD TO UNPREDICTABLE MESSAGES AND/OR APPLICATION FAILURES BEING ISSUED AT THE REMOTE DB2 LOCATIONS.
Local fix
Problem summary
**************************************************************** * USERS AFFECTED: All Distributed Data Facility (DDF) users. * * Specifically those who are planning to or * * are using z/OS applications which use * * packages bound with DBPROTOCOL(DRDACBF). * **************************************************************** * PROBLEM DESCRIPTION: -DISPLAY LOCATION DETAIL command * * shows ATT=CBF, T=R (requester) * * connections to another DB2 location, * * but -DISPLAY THREAD command does * * not show any threads accessing the * * remote location. * **************************************************************** * RECOMMENDATION: * **************************************************************** DB2 11 supports a capability called Cursor Block Fetch (CBF) which is activated by a z/OS DB2 requester application utilizing package(s) bound with the DBPROTOCOL(DRDACBF). The DB2 requester subsystem must be running V11 NFM or higher. Each read-only cursor operation performed by the application against another DB2 location, running at least V11 NFM, is processed on its own connection to the remote DB2 location. Once a cursor operation at the server is exhausted or the application chooses to close the cursor before retrieving all the rows of the query, the DB2 requester attempts to terminate the connection to the remote location. However, due to an internal DB2 logic error, the attempt to terminate the connection may not be processed correctly and no error indication is returned to the requesting z/OS application. Thus, once the requesting application thread terminates, a -DISPLAY LOCATION DETAIL command report may show that ATT=CBF, T=R connections still exist against the remote DB2 location even though the -DISPLAY THREAD(*) DETAIL command report suggests that no threads are associated to the connections. These connections are deemed to be orphan connections because no thread is currently using them and either a recycle of the DDF requester, or a Vary TCPIP Drop (V TCPIP,,DROP) command against each connection, will eliminate them. Note: While the connections remain active in the DB2 requester subsystem, corresponding connections will also be active in the serving DB2 subsystem. These server connections will also be associated to active DBATs. These DBATs may therefore hold resources for an extended period of time (until the connections are closed or the DBATs are canceled) which may lead to various unpredictable symptoms at the server location.
Problem conclusion
DB2 11 for z/OS has been changed to correctly process the termination of CBF connections to remote DB2 locations.
Temporary fix
Comments
APAR Information
APAR number
PI78280
Reported component name
DB2 OS/390 & Z/
Reported component ID
5740XYR00
Reported release
B10
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt / Xsystem
Submitted date
2017-03-15
Closed date
2017-04-06
Last modified date
2017-05-01
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
UI46258
Modules/Macros
DSNLCCNR
Fix information
Fixed component name
DB2 OS/390 & Z/
Fixed component ID
5740XYR00
Applicable component levels
RB10 PSY UI46258
UP17/04/24 P F704
Fix is available
Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.
[{"Business Unit":{"code":"BU059","label":"IBM Software w\/o TPS"},"Product":{"code":"SSEPEK","label":"Db2 for z\/OS"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"11.0","Edition":"","Line of Business":{"code":"LOB10","label":"Data and AI"}},{"Business Unit":{"code":"BU054","label":"Systems w\/TPS"},"Product":{"code":"SG19M","label":"APARs - z\/OS environment"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"11.0","Edition":"","Line of Business":{"code":"","label":""}}]
Document Information
Modified date:
01 May 2017