CONTROL BLOCK NAME = DFHWSTDS
NAME OF MATCHING PLS CONTROL BLOCK = None
DESCRIPTIVE NAME = CICS TS (XRF) - Takeover Parameter Area
Licensed Materials - Property of IBM
Restricted Materials of IBM
5655-Y04
(C) Copyright IBM Corp. 1985
FUNCTION =
The Takeover Parameter Area is a storage area belonging to
the CAVM TCB which is used to keep copies of the parameters
CICS specified on the TAKEOVER request that the CAVM TCB
is currently working on. DFHWSRTR makes the copies of the
TAKEOVER parameters while running under the CICS TCB and
the requesting TCA. If a subsequent failure in this TCA
should lead to the freeing of the storage it owns, the
CAVM TCB's processing of the TAKEOVER request will not be
affected.
Each XRF BACKUP system has a single TAKEOVER parameter area.
To avoid the problems which might arise from concurrent use
of the Takeover Parameter Area, the CAVM TCB does not
reference it unless the POST bit in WCSTXECB is 1, whereas
the CICS TCB does not reference it unless this bit is 0 and
also issues a CICS ENQ on WCSTCECB to serialise with other
CICS TCAs which might be issuing TAKEOVER requests.
LIFETIME =
The Takeover Parameter Area is created by DFHWSXPI when a
BACKUP system signs on to CAVM and is destroyed by
DFHWSTKV during TAKEOVER processing.
STORAGE CLASS =
Non-CICS storage. In MVS subpool 0 above 16M line.
LOCATION =
Field WCSTKVPP in the XRF Static Area (DFHWCSDS) contains
a pointer to the Takeover Parameter Area.
INNER CONTROL BLOCKS =
None.
NOTES :
DEPENDENCIES = S/370
RESTRICTIONS =
None.
MODULE TYPE = Control block definition
--------------------------------------------------------------------
EXTERNAL REFERENCES =
None.
DATA AREAS =
None.
CONTROL BLOCKS =
None.
GLOBAL VARIABLES (Macro pass) =
None.
--------------------------------------------------------------------
Table 1.
| Offset Hex |
Type |
Len |
Name (Dim) |
Description |
| (0) |
STRUCTURE |
0 |
TKVPA |
TAKEOVER parameter area |
| (0) |
HALFWORD |
2 |
TKVFUNCM |
Copy of TAKEOVER modifier from State Management parameter list |
| (2) |
HALFWORD |
2 |
|
Reserved - must be zero |
| (4) |
FULLWORD |
4 |
TKVINST# |
Instance no. of ACTIVE system to be taken over |
| (8) |
FULLWORD |
4 |
TKVVER# |
Version no. of ACTIVE system to be taken over (ignored if pre-emption is requested) |
| (C) |
FULLWORD |
4 |
TKVJTMTL |
Time limit for termination of the ACTIVE job after which operator assistance is sought (seconds) |
| (10) |
FULLWORD |
4 |
TKVMSGL |
Length of TAKEOVER message to send to the ACTIVE job |
| (14) |
CHARACTER |
128 |
TKVMSG |
TAKEOVER message for ACTIVE job |
| (14) |
1..1 .1.. |
|
TKVPALEN |
"*-TKVPA" |