A fix is available
APAR status
Closed as program error.
Error description
VSAM Record Management has a header block to keep track of storage that is acquired by VSAM for internal processing. The routine that assigns this storage has a small timing hole that can enable two requests to think they own the same storage. This causes overlay type symptoms. SYMPTOMS: ABEND0C4 in IDA019L1 WSHD Garbage in RPL feedback word
Local fix
Problem summary
**************************************************************** * USERS AFFECTED: All users of VSAM Record Management that * * utilize VSAM Compressed data sets or data * * sets that have alternate indexes. * **************************************************************** * PROBLEM DESCRIPTION: A failure to serialize access to * * work storage used by VSAM requests * * can result in 2 requests using the * * same storage simultaneously. * * Unpredictable results can occur * * including apparent overlays, ABENDS * * and incorrect RPL feedback codes. * **************************************************************** * RECOMMENDATION: Apply PTFs. * **************************************************************** A header control block is used to serialize the assignment of internal work storage used by VSAM. A small window exists that can cause two requests to be assigned the same storage.
Problem conclusion
The procedure in IDA019RX that assigns this work storage has been changed to utilize only registers when setting up for a Compare and Swap on the assignment of the block of storage.
Temporary fix
********* * HIPER * *********
Comments
APAR Information
APAR number
OA24071
Reported component name
DFSMS VSAM MEDA
Reported component ID
5695DF106
Reported release
1K0
Status
CLOSED PER
PE
NoPE
HIPER
YesHIPER
Special Attention
NoSpecatt / Xsystem
Submitted date
2008-02-15
Closed date
2008-03-19
Last modified date
2010-11-17
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
UA40125 UA40126 UA40127
Modules/Macros
IDA019RX
Fix information
Fixed component name
DFSMS VSAM MEDA
Fixed component ID
5695DF106
Applicable component levels
R1K0 PSY UA40125
UP08/06/27 P F806
R180 PSY UA40126
UP08/06/27 P F806
R190 PSY UA40127
UP08/06/27 P F806
Fix is available
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[{"Business Unit":{"code":"BU054","label":"Systems w\/TPS"},"Product":{"code":"SG19M","label":"APARs - z\/OS environment"},"Platform":[{"code":"PF054","label":"z\/OS"}],"Version":"1K0"}]
Document Information
Modified date:
09 January 2021