To use some DB2® stored
procedures, you must implement Resource Recovery Services (RRS). RRS
is a sync point manager program that coordinates two-phase commit
processing. DB2 requires
that RRS be active because WLM-managed stored procedure address spaces
use the RRS attachment facility (RRSAF).
About this task
RRS records events for protected resources
in log streams that are managed by a z/OS® component
called the system logger. The following table identifies the log streams
that RRS uses, where gname can be your Sysplex
name or any name in a non-Sysplex environment:
Table 1. Log streams that RRS uses| Log stream type |
Log stream name |
Content |
|---|
| Main unit-of-recovery log state stream |
ATR.gname.MAIN.UR |
The state of active units of recover (URs).
RRS periodically moves this information into the RRS delayed UR state
log when UR completion is delayed. |
| Delayed unit-of-recovery log state stream |
ATR.gname.DELAYED.UR |
The state of active URs, when UR completion
is delayed. |
| Resource manager data log stream |
ATR.gname.RM.DATA |
Information about the resource managers that
use RRS services. |
| Restart log stream |
ATR.gname.RESTART |
Information, which is needed during restart,
about incomplete URs. This information enables a functioning RRS instance
to assume remaining incomplete work from an RRS instance that failed. |
| Archive log stream |
ATR.gname.ARCHIVE |
Information about completed URs. This log stream
is optional, but recommended. |
All of these log streams are required except for the archive
log stream. RRS does not start if it is not able to connect to the
required log streams.
In a Sysplex environment, these log streams
are shared by the systems of the Sysplex.
Procedure
To implement RRS for stored procedures:
- Define the RRS log streams that are to be written, either
on disk or in the coupling facility by completing the following actions:
- If you are using the coupling facility, add definitions
for the RRS structures in the CFRM policy.
When you
are use coupling facility log streams, each log stream needs to be
mapped to a coupling facility structure.
Example: The following example shows JCL that
updates the CFRM policy to add the RRS structures:
//DEFCFRM1 JOB MSGCLASS=X,TIME=10,MSGLEVEL=(1,1),NOTIFY=&SYSUID
//STEP1 EXEC PGM=IXCMIAPU
//SYSPRINT DD SYSOUT=*
//SYSABEND DD SYSOUT=*
//SYSIN DD *
DATA TYPE(CFRM) REPORT(YES)
DEFINE POLICY NAME(CFRM18) REPLACE(YES)
CF NAME(CF01)
TYPE(009672)
MFG(IBM)
PLANT(02)
SEQUENCE(000000040104)
PARTITION(1)
CPCID(00)
DUMPSPACE(2048)
CF NAME(CF02)
TYPE(009672)
MFG(IBM)
PLANT(02)
................
................
................
STRUCTURE NAME(RRS_ARCHIVE_1)
INITSIZE(8000)
SIZE(16000)
PREFLIST(CF1,CF2)
REBUILDPERCENT(5)
STRUCTURE NAME(RRS_RMDATA_1)
INITSIZE(8000)
SIZE(16000)
PREFLIST(CF1,CF2)
REBUILDPERCENT(5)
STRUCTURE NAME(RRS_MAINUR_1)
INITSIZE(8000)
SIZE(16000)
PREFLIST(CF1,CF2)
REBUILDPERCENT(5)
STRUCTURE NAME(RRS_DELAYEDUR_1)
INITSIZE(8000)
SIZE(16000)
PREFLIST(CF1,CF2)
REBUILDPERCENT(5)
STRUCTURE NAME(RRS_RESTART_1)
INITSIZE(8000)
SIZE(16000)
PREFLIST(CF1,CF2)
REBUILDPERCENT(5)
- Define the log streams in the system logger policy by
using the IXCMIAPU utility. This utility program is provided in the
SYS1.MIGLIB system library.
If you are using the coupling
facility, also define the structures in the system logger policy.
You can map each log stream to a single structure or you can map log
streams of like data types to the same structure.
Example of defining coupling facility log streams: The following example JCL shows definitions for coupling
facility structures and RRS log streams. In this case, each RRS log
stream is mapped to a structure.
//STEP1 EXEC PGM=IXCMIAPU
//SYSPRINT DD SYSOUT=*
//SYSIN DD *
DATA TYPE(LOGR) REPORT(YES)
DEFINE STRUCTURE NAME(RRS_ARCHIVE_1) LOGSNUM(1)
MAXBUFSIZE(64000) AVGBUFSIZE(262)
DEFINE STRUCTURE NAME(RRS_RMDATA_1) LOGSNUM(1)
MAXBUFSIZE(1024) AVGBUFSIZE(252)
DEFINE STRUCTURE NAME(RRS_MAINUR_1) LOGSNUM(1)
MAXBUFSIZE(64000) AVGBUFSIZE(158)
DEFINE STRUCTURE NAME(RRS_DELAYEDUR_1) LOGSNUM(1)
MAXBUFSIZE(64000) AVGBUFSIZE(158)
DEFINE STRUCTURE NAME(RRS_RESTART_1) LOGSNUM(1)
MAXBUFSIZE(64000) AVGBUFSIZE(158)
DEFINE LOGSTREAM
NAME(ATR.SANDBOX.ARCHIVE) STRUCTNAME(RRS_ARCHIVE_1)
LS_DATACLAS(SHARE33)
HLQ(LOGR) MODEL(NO) LS_SIZE(1024)
LOWOFFLOAD(0) HIGHOFFLOAD(80) STG_DUPLEX(NO)
RETPD(15) AUTODELETE(YES)
DEFINE LOGSTREAM
NAME(ATR.SANDBOX.RM.DATA) STRUCTNAME(RRS_RMDATA_1)
LS_DATACLAS(SHARE33)
HLQ(LOGR) MODEL(NO) LS_SIZE(1024)
LOWOFFLOAD(0) HIGHOFFLOAD(80) STG_DUPLEX(NO)
RETPD(15) AUTODELETE(YES)
DEFINE LOGSTREAM
NAME(ATR.SANDBOX.MAIN.UR) STRUCTNAME(RRS_MAINUR_1)
LS_DATACLAS(SHARE33)
HLQ(LOGR) MODEL(NO) LS_SIZE(1024)
LOWOFFLOAD(0) HIGHOFFLOAD(80) STG_DUPLEX(NO)
RETPD(15) AUTODELETE(YES)
DEFINE LOGSTREAM
NAME(ATR.SANDBOX.DELAYED.UR) STRUCTNAME(RRS_DELAYEDUR_1)
LS_DATACLAS(SHARE33)
HLQ(LOGR) MODEL(NO) LS_SIZE(1024)
LOWOFFLOAD(0) HIGHOFFLOAD(80) STG_DUPLEX(NO)
RETPD(15) AUTODELETE(YES)
DEFINE LOGSTREAM
NAME(ATR.SANDBOX.RESTART) STRUCTNAME(RRS_RESTART_1)
LS_DATACLAS(SHARE33)
HLQ(LOGR) MODEL(NO) LS_SIZE(1024)
LOWOFFLOAD(0) HIGHOFFLOAD(80) STG_DUPLEX(NO)
RETPD(15) AUTODELETE(YES)
/*
Example of defining disk log streams: The
following example JCL shows definitions for RRS log streams on disk.
/DEFSTREXECPGM=IXCMIAPU
//SYSPRINT DDSYSOUT=A
//SYSINDD *
DATA TYPE(LOGR)
DEFINE LOGSTREAM NAME(ATR.PLEX1.MAIN.UR)
LOWOFFLOAD(60)
HIGHOFFLOAD(80)
DASDONLY(YES)
HLQ(TEST)
LS_SIZE(1024)
LS_DATACLAS(VSAMLS)
STG_SIZE(1024)
DEFINE LOGSTREAM NAME(ATR.PLEX1.DELAYED.UR)
LOWOFFLOAD(60)
HIGHOFFLOAD(80)
DASDONLY(YES)
HLQ(TEST)
LS_SIZE(960)
LS_DATACLAS(VSAMLS)
STG_SIZE(960)
DEFINE LOGSTREAM NAME(ATR.PLEX1.ARCHIVE)
LOWOFFLOAD(0)
HIGHOFFLOAD(80)
DASDONLY(YES)
HLQ(TEST)
LS_SIZE(960)
LS_DATACLAS(VSAMLS)
AUTODELETE(YES)
RETPD(2)
STG_SIZE(2000)
DEFINE LOGSTREAM NAME(ATR.PLEX1.RM.DATA)
LOWOFFLOAD(60)
HIGHOFFLOAD(80)
DASDONLY(YES)
HLQ(TEST)
LS_SIZE(192)
LS_DATACLAS(VSAMLS)
STG_SIZE(192)
DEFINE LOGSTREAM NAME(ATR.PLEX1.RESTART)
LOWOFFLOAD(60)
HIGHOFFLOAD(80)
DASDONLY(YES)
HLQ(TEST)
LS_SIZE(960)
LS_DATACLAS(VSAMLS)
STG_SIZE(960)
- If you are using coupling facility log streams, compile
and link-edit the changed CFRM policy.
- If you are using coupling facility log streams, activate
the updated CFRM policy in your Sysplex by using the following operator
command:
SETXCF START,POLICY,TYPE=CFRM,POLNAME=polname
- Establish the priority for RSS within the WLM policy.
The RRS priority needs to be equal to or higher than the
dispatching priority of DB2.
You can use the SYSSTC service class for the RRS address space to
achieve a higher dispatching priority.
- Move the ATRRRS procedure that is supplied by IBM® from SYS1.SAMPLIB to your SYS1.PROCLIB as
member RRS, and make any necessary changes. This JCL procedure
is used to start RRS.
You can use a member name other than RRS,
but the first four characters of this name must match the subsystem
name that you specify in the IEFSSNxx member of
SYS1.PARMLIB in the next step.
The GNAME value in the procedure
must match the gname that you specified when defining
the log streams. The default value for gname at
RRS startup is the Sysplex name.
Example: The following example shows a sample
procedure to start RRS.
//RRS PROC GNAME='',CTMEM=''
//RRS EXEC PGM=ATRIMIKE,REGION=0M,TIME=NOLIMIT,
// PARM='GNAME=&GNAME CTMEM=&CTMEM'
//
- Define RRS as a subsystem to z/OS by editing
the active IEFSSNxx member of SYS1.PARMLIB to include
the following entry:
SUBSYS SUBNAME(RRS) /* RESOURCE RECOVERY SERVICES */
The
subsystem name can be RRS or any other name that you choose. However,
the first four characters (or fewer characters if the name is shorter)
must match the name of the JCL procedure to start RRS.
- Start RRS by using the following operator command:
START RRS
If you subsequently need
to stop RRS, use one of the following operator commands:
- SETRRS CANCEL
- SETRRS SHUTDOWN
If neither of these commands stops RRS, use the FORCE
RRS,ARM command. In this command, RRS is the subsystem name
that your installation assigned to RRS in PARMLIB member IEFSSNxx.