A fix is available
APAR status
Closed as program error.
Error description
You have defined a recoverable ESDS file with no XFCLDEL exit active. If a task tries to backout an ADD to the file then this will fail with message DFHFC4701, failure code x'40'. If this occurs for many thousands of tasks then this can lead to a region outage. A subsequent emergency restart will attempt to reconstruct these units of work and rebuild their locks. The last set of messages you see are: DFHLG0747I System log scan continuing, n,nnn,nnn records processed The large number of shared locks required against the FCT can result in another outage. . Additional Keywords: KIXREVACC UNLOCK_SHARED
Local fix
Problem summary
**************************************************************** * USERS AFFECTED: All CICS users. * **************************************************************** * PROBLEM DESCRIPTION: CICS is unresponsive following the * * accumulation of backout failures for * * UOWs which performed write operations * * to a VSAM ESDS. * **************************************************************** * RECOMMENDATION: * **************************************************************** CICS is required to back out a unit of work that performed a write operation to a recoverable VSAM ESDS. However no XFCLDEL global user exit is enabled and started. As a consequence a backout failure occurs and the UOW is shunted. If this occurs many thousands of times against the same file this may lead to CICS becoming unresponsive. This is because the number of holders of the shared FCT lock has exceeded 32767. Subsequent unlock attempts result in a tight loop within CICS lock manager. In the reported case this was during an activity keypoint under a CSKP task. A subsequent emergency restart reconstructs these UOWs and the same situation can occur then when more than 32767 UOWs have shared the FCT lock once more. Additional keywords: msgdfhfc0578 msgdfhfc0579 fc0578 fc0579
Problem conclusion
DFHFCFS has been modified to issue a new informational message, DFHFC0578, if a recoverable VSAM ESDS or BDAM data set is opened when no XFCLDEL global user exit program is enabled. DFHFCMT has been modified to issue a new informational message, DFHFC0579, when the last XFCLDEL global user exit program is disabled. The CICS Transaction Server Version 5 Release 1 CICS Messages and Codes Vol 1 manual (GC34-2861-00) will be updated as follows. In Chapter 4. DFH messages - DFH01 to DFHM, immediately after the description of DFHFC0577, the descriptions of messages DFHFC0578 and DFHFC0579 will be added: DFHFC0578 applid File Control has opened file filename which is a recoverable filetype, however no XFCLDEL global user exit program is enabled. Explanation: If CICS is required to back out a unit of work that performed a write operation to a VSAM ESDS, or a BDAM data set, a backout failure will occur. System action: None. The message is informational. User response: To prevent a backout failure in the case described above, enable and start a suitable XFCLDEL exit program. For further information, refer to Exit XFCLDEL, file control logical delete exit. Module: DFHFCFS Message inserts: 1. applid 2. filename 3. filetype Destination: Console DFHFC0579 applid The last XFCLDEL global user exit program has been disabled. Explanation: As the result of a DISABLE PROGRAM command, there are no XFCLDEL global user exit programs enabled. If CICS is required to back out a unit of work that performed a write operation to a VSAM ESDS, or a BDAM data set, a backout failure will occur. System action: None. The message is informational. User response: To prevent a backout failure in the case described above, enable and start a suitable XFCLDEL exit program. For further information, refer to Exit XFCLDEL, file control logical delete exit. Module: DFHFCMT Message inserts: 1. applid Destination: Console The CICS Transaction Server Version 5 Release 2 CICS Messages and Codes Vol 1 manual (GC34-7283-00) will also be updated. Immediately after the description of DFHFC0577 in Chapter 4. DFH messages - DFH01 to DFHM, descriptions of messages DFHFC0578 and DFHFC0579 will be added, as listed above.
Temporary fix
FIX AVAILABLE BY PTF ONLY
Comments
×**** PE15/08/13 FIX IN ERROR. SEE APAR PI45284 FOR DESCRIPTION
APAR Information
APAR number
PI23986
Reported component name
CICS TS Z/OS V5
Reported component ID
5655Y0400
Reported release
800
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt / Xsystem
Submitted date
2014-08-15
Closed date
2015-01-20
Last modified date
2015-08-21
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
UI24536 UI24537
Modules/Macros
DFHFCFS DFHFCMT DFHMEFBC DFHMEFBE DFHMEFBK DFHSIC1 DFHUEM DFHUEXIT
GC34286100 | GC34728300 |
Fix information
Fixed component name
CICS TS Z/OS V5
Fixed component ID
5655Y0400
Applicable component levels
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":"BU058","label":"IBM Infrastructure w\/TPS"},"Product":{"code":"SSGMGV","label":"CICS Transaction Server"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"5.1","Line of Business":{"code":"LOB35","label":"Mainframe SW"}}]
Document Information
Modified date:
22 July 2020