Region Definitions

The Region Definitions (RD) define all the parameters that CICS® uses to initialize a region. The RD contains both static and dynamic information that the CICS region requires at startup. This is both control and initialization information.

This topic lists a basic set of RD attributes. The remainder, which supplies the information that is required for starting up an SFS, are listed in Region Definitions (RD) for file server. The following attributes are described in this topic:

Note: Attribute names appear as they are used on the command line, followed in parentheses by the descriptions that are used by the AIX® System Management Interface Tool (SMIT).

ABDump (Should CICS system be dumped for ASRB abends)

This attribute specifies whether a system dump or a transaction dump is taken if an ASRB abend occurs. If the ABDump attribute is set to yes, (and both the SysDump attribute and the TD TransDump attribute for a transaction are set to yes), a system dump occurs. If the ABDump attribute is set to no (and the TransDump attribute is set to yes for the transaction), a transaction dump is taken. The default value is yes.

AllowDebugging (Allow use of the application debugging tool) (CICS for AIX only)

This attribute specifies whether the use of the application debugging tool is permitted. The possible values are yes and no. The default value is no.

AmendCounter (Number of updates)

This attribute is reserved for CICS internal use.

AutoinstallMode (Mode for autoinstallation of terminals)

This attribute specifies how terminals are autoinstalled. The possible values are old_style, default (the default), and no_netname_check. The value old_style matches the behavior of earlier versions of CICS on Open Systems. The value no_netname_check disables all checks for the uniqueness of the net names, allowing the region to install terminals more quickly than is permitted by the value default, which guarantees that net names are unique.

CARPDelayHours (ATI purge interval (hours))

This attribute specifies how often, in hours, CICS schedules the transaction that deletes ATI requests that have been queued for longer than the period that is specified by the PurgeDelayPeriod or the ProtectPurgeDelayPeriod attribute. The default value is 8.

CheckpointInterval (Number of records logged between checkpoints)

This attribute specifies the number of records that are written to the log file between checkpoints. A low number of writes results in diminished performance but shortens recovery time following errors. A high number reverses these effects. The default value is 1000.

ClassTableSize (Hash sizes CD, FD, PD, RD, TSD, WD, TD, TDD, XAD, UD, MD, JD, LD, GD, OD, MQD, TCD)

This attribute specifies a comma-separated list of numbers that CICS uses to control the size of the internal tables holding resource definitions. The sequencing of the list is as follows: CD, FD, PD, RD, TSD, WD, TD, TDD, XAD, UD, MD, JD, LD, GD, OD, MQD, TCD. The values of this attribute specify the number of tables in which the entries for every resource definition is stored. Always set the number for RD and MD to 1, and set JD to the maximum number of user journals that you expect your region to support. The values that you assign to the other resource definitions depend on the number of entries that you expect in those resource classes, which can include autoinstalled entries. For example, suppose you explicitly define four connection definitions (CD) for back end regions and expect 12 000 autoinstalled connection definitions from clients, for a total of 12 004 connection definitions. Setting the ClassTableSize for CD to 50 in this case results in 50 tables with approximately 240 entries per table, a size that is manageable and makes the most efficient use of system resources. You can tune the values of this attribute by using statistical information. For further information about statistics, see Generating statistics and Statistics reports. The default ClassTableSize values are 5, 50, 50, 1, 50, 50, 50, 20, 5, 50, 1, 20, 5, 5, 20, 15, 12..

CoreDumpName (Directory in which Core Dump output is written)

This attribute specifies the name of a subdirectory to which core images are written in the event of an irrecoverable CICS abnormal termination. The subdirectory is located under DumpName. The default value is dir1.

CUBSDelayMinutes (Rescheduling interval for blocked ATIs (mins))

This attribute specifies the intervals at which the CICS-supplied transaction CUBS checks Temporary Storage (TS) in order to recover Interval Control Elements (ICEs) as part of an autostart process. If TS is not available, the system makes periodic checks and recovers ICEs when it finds that TS queues are available. The value of CUBSDelayMinutes is set in minutes. The default value is 5.

CWASize (Common Work Area Size)

This attribute specifies the number of bytes that is to be allocated to the Common Work Area (CWA). The maximum size for the work area is 3584 bytes. The default value is 512.

DateForm (Format date for FORMATTIME)

This attribute specifies the date format that is required for the EXEC CICS FORMATTIME command. Formats can be specified by three possible values:

mmddyy: month-day-year
mmddyyyy: month-day-year
ddmmyy: day-month-year
ddmmyyyy: day-month-year
yymmdd: year-month-day
yyyymmdd: year-month-day

The default value is ddmmyy.

DefaultUserId (Name of the default user identifier)

This attribute specifies the default user ID for the region. The default user ID is used for tasks that are not associated with a signed-on user ID. It is also used under the following conditions for tasks that are run by a user:

When an attempt to sign on by using CESN or CESL fails.
When CRTE is used to route to another system, and CESF is used to log off, the default user ID is used until either CESN or CESL is used to log back on.

For intersystem requests, the following attributes are used in conjunction with the DefaultUserId attribute:

The CD LinkUserID attribute, in addition to the TSL and RSL keys that are defined in the UD entry for the user ID that is specified with this attribute.
The CD RemoteSysSecurity attribute.
The CD TSLKeyMask and RSLKeyMask attributes.

For more information about how this attribute is used for intersystem requests, see Configuring intersystem security.

Note: Provide a UD entry for the default user ID. Otherwise, the message ERZ045006W occurs each time that a user who is signed on as the default user invokes a transaction. Also, because remote users can be given this default user ID, it is recommended that you assign to it only the minimum required TSL and RSL keys for local users to run at the security level that is needed when the default user ID is used. For more information about how remote users are assigned security keys, see Configuring intersystem security.

The default value is CICSUSER.

DumpName (Region subdirectory in which dump output is written)

This attribute specifies the name of the directory that contains the subdirectories in which CICS dumps are written. The default value is dumps.

DumpName directory must be under the /var/cics_regions/ region_name directory.

CICS uses the available subdirectories in alphabetic sequence. By default, all CICS dumps are written to dumps/dir1 because the default value of the CoreDumpName attribute is dir1.

DumpRemoteInfo (Should remote information be dumped to CRTI)

This attribute specifies whether remote task information should be dumped into CRTI. If this attribute is set to yes then the remote task information is written to CRTI. The default value is no.

EAMLoad (Do you want to use External Authentication Manager)

This attribute specifies whether CICS loads the External Authentication Manager (EAM) program at startup. If this attribute is set to no, CICS does not load the EAM program. If the value is yes, CICS loads the EAM program. The default value is no. For information about the EAM, see Using an External Authentication Manager.

EAMModule (Name of EAM Module)

This attribute specifies the EAM program path and name. The default value is "".

For information about the EAM, see Using an External Authentication Manager.

EnableTaskInfo (Should task information be passed to the linked region)

This attribute specifies whether task information should be passed to the linked region. If this attribute is set to yes then the current task information and the originating task information if any is passed to the remote region connected using EXEC CICS LINK. The default value is no.

ESMLoad (Do you want to use an External Security Manager)

This attribute specifies whether CICS loads the External Security Manager (ESM) program at startup. If this attribute is set to no, CICS does not load the ESM program. If the value is yes, CICS loads the ESM program. The default value is no.

For information about the ESM, see Using an External Authentication Manager.

ESMModule (Name of ESM Module)

This attribute specifies the ESM program path and name. The default value is "".

For information about the ESM, see Using an External Authentication Manager.

FileReadIntegrity

This attribute defines the read integrity required for files defined in File Definition. The possible values are yes and no. The default value is no.

With attribute value as yes, CICS can read images of database rows that are not locked.
With attribute value as no, CICS can read images of database rows that are locked for update.

This attribute is applicable for DB2 only.

FileRSLCheck (Type of RSL checking for Files)

This attribute specifies whether the region uses an External Security Manager (ESM) instead of CICS-provided resource security for files. The possible values are internal and external. If external is specified, the attribute RSLCheck must be set to external in the required Transaction Definitions (TD) entries. In addition, if external security checking is required, the ESMLoad and ESMModule attributes must be set to configure the ESM; otherwise, only internal security checking occurs. The default value is external.

FileSystemType

This attribute specifies the type of file system that is to be used for CICS queues and files. The value must be either SFS, DB2®, or ORACLE. The default value is SFS.

Groups (Startup groups)

This attribute specifies a list of group names that are used to cold start the region. Each name is specified in a string of no more than eight bytes. A maximum of 10 groups is allowed. Specify the groups as a comma-separated list. The default value is "", which results in the installation of all database entries with a default group of "".

HTMLBrowser (HTML Browser for help text) (CICS for Windows only)

This attribute specifies the fully qualified path name of the HTML browser that is used to view the help files for the CICS-supplied transactions when a cicslterm terminal is used. The location of the HTML files is specified by the environment variable CICS_CST_HTML.

IIOPGroupHost (IIOP Server Group TCP/IP hostname)

This attribute specifies the TCP/IP host name for the server group, which is inserted into the interoperable object references (IORs) for workload-managed objects. The dynamic DNS resolves this group name to a specific server address. An example value for IIOPGroupHost is group1.cics.site.crp.com.

IIOPGroupPort (IIOP Server Group TCP/IP port number)

This attribute specifies the TCP/IP port number, which is inserted into the IORs for workload-managed objects. For a dynamic DNS configuration, this is the same port number as is defined for the CICS IIOP listener. All CICS IIOP servers in the same server group must therefore use the same port number for the CICS IIOP listener. An example value is 9876.

IIOPGroupSSLPort (IIOP Server Group TCP/IP port number for SSL support)

This specifies the TCP/IP port number, which is inserted into the IORs for objects that are SSL enabled and workload managed. If SSL support is required with workload management, this attribute must be set. All servers in the group must have an IIOP SSL listener defined. An example value is 8765.

IIOPGroupUUID (IIOP Server Group Name)

This attribute specifies a part of the object key and takes the place of the (server-specific) universal unique identifier (UUID). This field in the object key is used to validate incoming IIOP requests. For objects that are not configured for workload management, a check is made to determine whether the UUID in the request matches the UUID of the server. If the object is configured for workload management, the group UUIDs must match (the IIOP request can be handled by any server in the group). Set it to a suitable unique name that is defined by the administrator (for example, Group1). The maximum length allowed for this name is 36 characters.

IIOPObjrefsVersion (IIOP Version for generated object references)

This attribute specifies the IIOP version level that is supported. The default is 1.1, which means IIOP version 1.1. This level is required for SSL support. The only other supported value is 1.0, for IIOP version 1.0.

IIOPRequestTimeout (Outbound IIOP request/response timeout value (secs))

This attribute specifies the number of seconds an IIOP request waits for a response before raising an error. A value of 0 (zero) indicates an infinite wait. The default is 100.

IntrospectInterval (Interval between region consistency checks (mins))

This attribute specifies, in minutes, the time interval between periodic checks to monitor the integrity of a region. The value can be specified in the range 0 (zero) through 1440. The value 0 switches off integrity checking. Checking integrity at frequent intervals decreases performance. The default value is 10.

IntrospectLevel (Level of checking to perform on region)

In this release of CICS, this attribute has a fixed value of minimal.

ISCDelayMinutes (Retransmission interval for queued ATIs (mins))

This attribute specifies, in minutes, how often CICS attempts to send Automatic Transaction Initiation (ATI) requests to a target system when the requests have been locally queued because the target system is unavailable. It also specifies the interval between instances of the CICS private transaction CFTS, which is used to delete shipped terminal definitions, enabling resources to be freed. The default value is 10.

JournalRSLCheck (Type of RSL checking for Journals)

This attribute specifies whether an External Security Manager (ESM) or CICS-provided resource security is used for journals. The possible values are internal and external. If you require external security checking, you must also set the RSLCheck attribute to external in the required TD entries. In addition, the ESMLoad and ESMModule attributes must be set to configure the ESM; otherwise, only internal security checking occurs. The default value is external.

LoadDataNumBuckets (Number of LOADed data Address Hash Buckets)

This attribute controls access to maps and tables by specifying the size of the hash table that CICS uses to find maps and tables in the task-shared pool. Set the value in accordance with the expected usage of your region. CICS rounds up the specified value to the nearest power of two, with a minimum value of 1. When setting this attribute, consider the trade-off between increased performance and increased use of storage space. You can tune the value of this attribute by using statistical information. For more information about statistics, see Generating statistics and Statistics reports. The default value is 512.

LocalLUName (Local LU name)

This attribute specifies the default SNA Logical Unit (LU) name for the region. It is used as the local LU name for the region that has local SNA support. It is also used as the local LU name for the region that has SNA support through a PPC Gateway server if the Gateway Definitions (GD) entry for the PPC Gateway server has a null ("") setting for the GatewayLUName attribute.

The LU name can be a maximum of eight characters. The first character must be an uppercase alphabetic character (A through Z), and the subsequent characters must be either uppercase alphabetic characters or numeric characters (0 through 9). For example, the following values are valid for the local LU name:

A
CICS
CICSUNIX
MYLU

The following values are not valid.

9 (Begins with a number)
1CICS (Begins with a number)
CICSunix (Contains lowercase alphabetic characters)
MY-LU (Contains the unsupported character '-')

If the LocalLUName is blank (""), CICS sets it to the region name. The default value for LocalLUName is "".

Note: If you are configuring a listener definition with Protocol type set to IPIC, this field cannot be left blank and the local network name must be supplied

LocalNetworkName (Network name to which local region is attached)

This attribute specifies the network name to which the local region is attached. The value is specified in a maximum of eight characters. The default value is "".

LocalSysId (Region system identifier (short name))

This attribute specifies the short name of the CICS region (as used in the SYSID option of several CICS commands). Its value can be a maximum of four characters from the set A through Z, 0 through 9, dollar ($), and at sign (@). Lowercase alphabetic characters are converted to uppercase characters. The default value is ISC0.

MaxConsoleSize (Maximum size for a region console file)

This attribute specifies controls the size of the console.nnnnnn and the symrecs.nnnnnn files. The variable nnnnnn represents a number that is incremented every time a new console file is opened. A new console.nnnnnn file is written when a new CICS region is started or when the limit set in MaxConsoleSize has been reached.

If the value of MaxConsoleSize is set to 0, the console.nnnnnn and symrecs.nnnnnn files continue to grow within the space that your system allows. Set MaxConsoleSize to a size greater than 100 000 (approximately 100 KB). If you set a lower value than 1 000 000, the value is automatically reset to 100 000 during system initialization. When the upper limit is reached, two messages are issued, one explaining that the file is about to be closed, and the second giving the name of the new file. It is possible to use the cicstail command to tail the console file. When the file changes, cicstail switches to the new file.

For automatic archiving, a program can periodically check the contents of the console files and look for the message at the end indicating that the file has been closed.

The default value for MaxConsoleSize is 0.

Note: If user applications write data into the console file when the MaxConsoleSize is set, the size of the console file might be different and unpredictable.

MaxRegionPool (Region Pool Storage Size (bytes))

This attribute specifies the size of the region pool in bytes. This is a storage area that CICS uses to hold CICS-private region information. The value depends on the number of resources in your region, the volatility of these resources, and the level of transactional activity. For example, the default value of 3145728 is enough to start a region with two application servers.

To estimate an appropriate value, allow 1000 KB plus 50 KB for each application server (specified by the MaxServer attribute). For example, if MaxServer is set to 5, the calculation is 1000 KB + (50 KB * 5) = 1250 KB. If you are running the Front-End Programming Interface (FEPI), add 500 KB to this figure.

In a running region, check the statistics for region pool size. If the region pool size is close to the default setting, consider increasing the value for MaxRegionPool. The minimum value is 716800, and the maximum value is 2147483647 (2GB-1). The default value is 3145728.

When increasing the size of the region pool, you must consider the physical placement of the pool in a CICS process virtual memory map in relation to other areas of memory such as the Task Shared Pool. This physical placement is controlled by the RegionPoolBase attribute.

MaxServer (Maximum number of Application Servers to maintain)

This attribute specifies the maximum number of application servers that CICS uses to process transactions. The default value is 5.

MaxTaskCPU (Maximum milliseconds of user space CPU usage allowed for any task) (CICS on Open Systems only)

This attribute specifies the maximum time (in milliseconds) that is allowed for CPU use by all the transactions of a region. If you set the value to 0 (zero), no region-wide control of CPU usage exists. If the value is greater than zero, checks are made each time the transaction enters CICS through an EXEC CICS call command. The maximum value is 2**31 —1 (approximately 24 days of user space per CPU). For an individual transaction, you can set the MaxTaskCPU attribute in the Transaction Definitions to override the value that is set for this attribute. The default is 0.

MaxTaskCPUAction (Action to be taken when a task exceeds MaxTaskCPU) (CICS on Open Systems only)

This attribute specifies the action that is taken when a task exceeds the value of the MaxTaskCPU attribute. The values are abend or warning. When a task's CPU usage exceeds the value of MaxTaskCPU and MaxTaskCPUAction is set to warning, a warning message is added to the console.nnnnnn file. When the value is set to abend, the task abends. The default is warning.

MaxTaskPrivatePool (Task-private Storage Size (bytes))

This attribute specifies the amount of memory that is allocated for each process's task-private pool. The value depends on the sizes of EXEC CICS GETMAIN areas and CICS transaction programs. To maximize performance, storage areas are aligned on appropriate boundaries, which can cause more storage to be allocated than is used. When calculating this value, allow for this additional storage. The minimum value is 307200, the maximum value is 2147483647 (2 GB–1), and the default value is 1048576.

When increasing the size of this pool, you must consider the physical placement of the memory area in a CICS process virtual memory map in relation to the other areas of memory. On AIX, the physical placement can be controlled by the environment variable LDR_CNTRL=MAXDATA=o_maxdata. Setting the environment variable in the region environment file ensures that the process heap starts from 0x30000000 and that the segment starting from 0x20000000 is free for the stack and the loadable modules. Theo_maxdata value that is set in the environment variable specifies the offset value up to which the memory heap can extend, starting from 0x30000000. This heap will be shared by the TaskPrivatePool and other memory allocation that come from the heap. For example, setting o_maxdata to 0x20000000 makes 2 segments (512MB) available for the heap and the remainder for the shared memory. Setting the value of o_maxdata to 0x00000000 takes you back to the small memory model.

MaxTSHPool (Task-Shared Pool Storage Size (bytes))

This attribute controls the size of the task-shared pool. This is a storage area that CICS uses to hold information that two or more tasks need, whether running in CICS code or in the user programs.

The storage from this area is used for the following:

COMMAREAs
Common Work Area (CWA)
Terminal Input/Output Areas (TIOAs)
TCT User Areas (TCTUAs)
Main temporary storage
Maps and tables
Conversion templates
Temporary storage for unprotected STARTs

The value depends on the size of CICS-provided shared areas such as the Terminal Control Table User Areas (TCTUAs), the size of EXEC CICS GETMAIN SHARED areas, the number of MAIN temporary storage requests, and the volatility and levels of Basic Mapping Support (BMS) requests. For information about efficiency, see CICS application design considerations. The minimum value is 32768, the maximum value is 2147483647 (2GB-1), and the default value is 1048576.

When increasing the size of this pool, you must consider the physical placement of the memory area in a CICS process virtual memory map in relation to other areas of memory such as the Region Pool. This physical placement is controlled by the TaskSharedPoolBase attribute.

MinServer (Minimum number of Application Servers to maintain)

This attribute specifies the minimum number of application servers that CICS uses to process transactions. The default value is 1.

Modifiable (Protect resource from modification)

This attribute specifies whether amending or deleting the permanent database entry is permitted. If the attribute is set to yes, the entry can be amended or deleted. If the Modifiable attribute is set to no, the entry cannot be modified or deleted. To modify the entry, reset the attribute to yes. After amending the entry, set the Modifiable attribute back to no. The default value is yes.

PCDump (Should CICS system be dumped for ASRA abends)

This attribute specifies whether a system dump or a transaction dump is taken if an ASRA abend occurs. The possible values are yes and no. If PCDump is set to yes and both the SysDump attribute and the TransDump attribute for a transaction are set to yes, a system dump occurs. If PCDump is set to no and TransDump is set to yes for the transaction, a transaction dump is taken. The default value is yes.

PostScanInterval (Interval to scan for hand posts (In seconds))

This attribute specifies the interval in seconds that CICS waits between initiating scans to locate a completed WAIT EVENT. The default is set to 0 (zero). For an event to be completed manually, this number must be greater than 0 (zero).

ProgramCacheSize (Maximum number of C or IBM® COBOL programs that can be cached)

This attribute specifies the maximum number of programs that can reside in one application server's program cache. A program is cached at the time it is loaded only if the Program Definitions (PD) Program Definitions (PD) attribute is set to yes and the number of cached programs in use has not reached the maximum number.

A resident program is not loaded again until one of the following occurs:

A SET PROGRAM COPY(PHASEIN) or SET PROGRAM PHASEIN command is issued.
The value of the Program Definitions (PD) Resident attribute is changed to no.
The cache is full and the program is removed to make room for a new entry. In this case, the least-recently used program is removed, leaving more-frequently used programs in the cache.

Because programs that are being used are not removed from the cache, it is recommended that the cache size allow programs at every logical level to be cached when using EXEC CICS LINK.

The default value is 0 (zero).

ProgramRSLCheck (Type of RSL checking for Programs)

This attribute specifies whether an External Security Manager (ESM) is used instead of CICS-provided resource security for programs. The possible values are internal and external. If you require external security checking, you must also set the RSLCheck attribute to external in the required TD entries. In addition, the ESMLoad and ESMModule attributes must be set to configure the ESM; otherwise, only internal security checking occurs. The default value is external.

ProtectPurgeDelayPeriod (Purge delay period for PROTECT requests (hours))

This attribute specifies the period, in hours, for locally queued ATIs with the PROTECT option specified to remain queued. Specify 0 to indicate that you do not want CICS to perform this purge function. The default value is 8.

PurgeDelayPeriod (Purge delay period for no PROTECT requests (hours))

This attribute specifies the period, in hours, for locally queued ATIs without the PROTECT option specified to remain queued. Specify 0 to indicate that you do not want CICS to perform this purge function. The default value is 8.

RDBMSInstance (specifies the name of the instance of DB2)

If the region is configured to use DB2 as its file system, this attribute specifies the name of the instance of DB2 and is used to set the DB2 environment variable DB2INSTANCE. If the cicsdb2conf command is used, this attribute is reset to the value that is specified by the -i parameter of the cicsdb2conf command. The default value is "".

RegionPoolBase (Region Pool base register) (AIX and Windows only)

This attribute specifies the address at which CICS attaches the segment that it uses for its region pool.

Changing this value can be necessary if, in addition to CICS, you are running a utility or an application (such as a database) that also uses shared memory. By changing the value of this attribute, you can ensure that the CICS shared memory segments do not overlap with those of your application.

If you use the cicsupdate command to change this value, you can specify it in either hexadecimal notation (for example, 0x70000000) or decimal notation (for example, 1879048192). If you use SMIT (CICS for AIX only) to change this value, enter it in decimal notation.

On CICS for AIX, the value of the RegionPoolBase attribute must be within the range 0x30000000 through 0xC0000000, and must be a multiple of 0x10000000. The default value is 0xA0000000.

On CICS for Windows, the value of the RegionPoolBase attribute must be less than 0x80000000. The size of the region pool is specified by the MaxRegionPool attribute. The area of memory that is defined by these two attributes must not overlap with the areas of any dynamic link libraries (DLLs) that are already loaded. If it does, you must change the RegionPoolBase value to an area of memory that is not in use. The default value is 0x70000000.

Note: The IBM TXSeries Administration Console does not recognize hex values for the RegionPoolBase attribute. Decimal values must be used when the IBM TXSeries Administration Console is used to set this attribute.

Do not specify the same value for this attribute as for the TaskSharedPoolBase attribute.

RegionPoolThreshold (Threshold for Region Pool short on storage (%age))

This attribute specifies a percentage of the region pool that must be exceeded for CICS to generate a warning message. The default value is 90.

ReleaseNum (CICS Release Number)

This attribute specifies the current CICS release number in four bytes. It is in the format 0XXX, where the first byte is a zero. This attribute is provided for information purposes only. If you try to change the attribute by using an editor program or the cicsupdate command, the change is ignored at region startup.

ResourceDescription (Resource description)

This attribute specifies this resource in a 30-byte string. The first 17 characters of this text value are used in the “Available CICS Regions” panel when you run the cicslterm command or the cicsteld command without specifying a region name. Specifying this value allows you to give this panel more meaning; otherwise, the default value “Region Definition” is used.

RPCListenerThreads (Number of threads for RPC requests)

This attribute specifies the number of threads that the RPC listener process cicsrl uses to listen for transaction and autoinstall requests from terminals and from CICS EPI applications. An RPC listener thread is generally occupied by a request for the time it takes to complete a transaction or an autoinstall. For more information about how this attribute can affect performance, see Improving performance by controlling the rate of requests to the RPC listener. The default value is 0, and the actual number of RPC listener threads is calculated as ten times the value of the MaxServer attribute.

However, the specified value or the calculated value must not exceed the operating system limit for the maximum number of supported concurrent threads.

On AIX, the maximum number of concurrent threads supported is 512.
On Linux®, the maximum number of concurrent threads supported is 16 384.

SafetyLevel (Level of protection against user corruption)

This attribute specifies the degree of protection that CICS provides for programs that are n this region. Possible values are none, normal, and guard (CICS for Windows only).

Note: SafetyLevel=normal is not supported on Windows for COBOL transactions. Setting SafetyLevel to normal or guard is recommended in development system only. This setting helps to detect issues related to applications writing beyond their allocated storage limits before the programs are moved to production. It is not recommended to set SafetyLevel to normal or guard in production system, as it might lead to performance over head and unexpected exceptions in CICS Application Server (CICSAS).

If SafetyLevel is set to none, CICS and user transactions can both access the region pool. If SafetyLevel is set to normal, only CICS transactions can access the region pool.

The guard setting is provided specifically for use on the Windows operating system, on which the normal SafetyLevel setting incurs significant performance costs. To lessen these performance costs, set SafetyLevel to guard, which causes only the first and last pages of the region pool to be protected. On CICS for AIX system, the guard setting is treated the same as the normal setting. The default value is none.

ServerIdleLimit (Time before Application Servers terminate (secs))

This attribute specifies the time, in seconds, that idle application servers are allowed to exist before CICS terminates them. CICS always ensures that the number of servers that is specified by MinServer attribute are available at all times. The default value is 300.

ServerMemCheckInterval (Time to monitor data segment size)

This attribute specifies the period of time in which the CICS application server process could record its data segment size, in seconds. A value of zero disables this warning facility. This facility is disabled by default. For information about when to use this facility, see Observing memory growth for application server processes.

ServerMemCheckLimit (Number of times to monitor data segment size)

This attribute specifies the number of times that the ServerMemCheckInterval must be done before CICS evaluates and reports or warns that a constant increase in the data segment size of the application server process has occurred. A value of zero disables this warning facility. This facility is disabled by default. For information about when to use this facility, see Observing memory growth for application server processes.

ServerSideTran

This attribute specifies whether SFS transactions are done internally within SFS. The value Yes indicates that the CICS system communicates with only a single SFS system and that the only intersystem communication that is supported is transaction routing. Communications using XA might become slower or might cause errors. The variable can be set to Yes for applications that depend only on a single SFS server, and for which no other Resource Managers are involved. This is valid only for the SFS file manager.

ShutdownProgList1 (Programs to execute at phase 1 of shutdown)

This attribute specifies a list of up to 10 programs that CICS runs automatically during the first stage of the two-stage CICS shutdown process. The value is a comma-separated list. Each program must have an entry in the Program Definitions (PD). The default value is "".

ShutdownProgList2 (Programs to execute at phase 2 of shutdown)

This attribute specifies a list of up to 10 programs that CICS runs automatically during the second stage of the two-stage CICS shutdown process. The value is a comma-separated list. Each program must have an entry in the Program Definitions (PD). The default value is "".

StartType (Startup type)

This attribute specifies the type of CICS system initialization that is required for the region. If the value is set to cold, CICS performs a cold start. If the value is set to auto, CICS uses the restart information that was written by the previous run of CICS, to restart the region from the state in which it was last shut down. If no restart information exists, CICS performs a cold start. If it is the first time the region is started, a cold start is automatically used. If the region has been started before, a warm start is automatically performed to ensure data integrity.

Note: When the cicscp start region command is issued, the command checks whether the region has previously been started. If the region has previously been started, the cicscp command only performs a warm start to ensure data integrity, regardless of the setting for the RDStartType attribute. You can override the value of StartType only by explicitly adding the setting StartType=cold when using the cicscp start region command (on all platforms), or the startsrc command (on CICS for AIX), or the cicsstart command (on all other CICS on Open Systems platforms).

StartupProgList (Programs to execute at startup)

This attribute specifies a list of up to 10 programs that CICS runs automatically during startup. The value is a comma-separated list. Each program must have an entry in the Program Definitions (PD).

Note: Resource security checking is not performed during the execution of the startup program.

The default value for StartupProgList is "".

StatFile (File or path for statistics)

This attribute specifies the absolute path name of the file into which CICS is to write statistical information. The default value is statsfile.

StatsRecord (Should stats be recorded at every interval)

This attribute specifies whether CICS is to collect statistical information every interval. The possible values are yes and no. The default value is yes. For more information about statistics, see Generating statistics and Statistics reports.

SufficesSupported (Should map names be suffixed)

This attribute specifies whether CICS uses terminal suffixing. The possible values are yes and no. The default value is yes.

SysDump (System dump on shutdown, SNAP dumps, ASRx abends)

This attribute specifies whether CICS records system dump information if an abnormal termination occurs. The possible values are yes and no. This attribute also determines whether CICS produces a dump at shutdown. In addition, for transaction abnormal terminations ASRA and ASRB, if the value of SysDump is set to yes, a system dump can also occur as explained in the descriptions of the attributes PCDump and ABDump. The default value is no.

TaskSharedPoolBase (Task-Shared Pool base register) (CICS for AIX and CICS for Windows only)

This attribute specifies the address at which CICS attaches the segment that it uses for its task-shared memory pool.

This value must possibly be changed if, in addition to CICS, you are running a utility or an application (such as a database) that also uses shared memory. By changing the value of this attribute, you can ensure that the CICS shared memory segments do not overlap those of your application.

On CICS for AIX, the value of the TaskSharedPoolBase attribute must be within the range 0x30000000 to 0xC0000000, and must be a multiple of 0x10000000. The default value is 0xB0000000.

On CICS for Windows, the value of the TaskSharedPoolBase attribute must be less than 0x80000000. The size of the task-shared pool is specified by the MaxTSHPool attribute. The area of memory that is defined by these two attributes must not overlap with areas of any dynamic link libraries (DLLs) that are already loaded. If it does, you must change the TaskSharedPoolBase value to an area of memory that is not in use. The default value is 0x79C00000.

Note: The IBM TXSeries Administration Console does not recognize hex values for the TaskSharedPoolBase attribute. Decimal values must be used when the IBM TXSeries Administration Console is used to set this attribute.

Do not specify the same value for this attribute as for the RegionPoolBase attribute.

TaskSHNumBuckets (Number of Task Shared Pool Address Hash Buckets)

This attribute controls access to the task-shared pool by specifying the size of the hash table that CICS uses to find items in this pool. Set the value in accordance with the expected usage of your region. CICS rounds up the value that you specify to the nearest power of two, with a minimum value of 512. The value that you supply depends on the expected usage of your region. When setting this attribute, consider the trade-off between higher performance and increased use of storage space. You can tune the value of this attribute by using statistical information. For more information about statistics, see Generating statistics and Statistics reports. The default value is 512.

TaskShPoolThreshold (Threshold for TSH Pool short on storage (%age))

This attribute specifies a percentage of the task-shared pool that must be exceeded for CICS to generate a warning message. The default value is 90.

TDPurgeInterval (Interval to clean up the Transient Data queue (in minutes))

This attribute specifies how frequently the transient data queues are purged. The value indicates, in minutes, the intervals at which the private transaction CTDP is activated. If the TDPurgeInterval attribute value is set to 0 (zero), the CTDP transaction runs at startup and every midnight. If the TDPurgeInterval attribute value is set to any other value, the CTDP transaction runs at startup and at the specified intervals. The default value is 0.

TemporaryStorageRSLCheck (Type of RSL checking for TSQs)

This attribute indicates whether the region uses an External Security Manager (ESM) instead of CICS-provided resource security for TS queues. The possible values are internal and external. If external is specified, the RSLCheck attribute must be set to external in the required TD entries. In addition, if external security checking is required, the ESMLoad and ESMModule attributes must be set to configure the ESM; otherwise, only internal security checking occurs. The default value is external.

TraceDirectorySystem (Directory under which CICS system writes trace data)

This attribute specifies the directory under which CICS writes files that contain system trace data. The default value is /var/cics_regions/regionName/dumps/dir1 (CICS on Open Systems) or \var\cics_regions\regionName\dumps\dir1 (CICS for Windows).

TraceDirectoryUser (Directory under which CICS writes user trace data)

This attribute specifies the directory under which CICS writes files that contain user trace data. The default value is /tmp (CICS on Open Systems) or \var\cics_tmp (CICS for Windows).

TraceFlagAux (Does CICS route system trace to files)

This attribute specifies whether CICS routes system trace to files. The possible values are on and off. This specification is in addition to other system-trace destinations that CICS uses. Files are placed in the directory that is specified by the TraceDirectorySystem attribute. The default value is off.

TraceFlagBuffer (Does CICS route system trace to a buffer)

This attribute specifies whether CICS routes system trace to a buffer. The possible values are on and off. This specification is in addition to other system-trace destinations that CICS uses. The default value is on.

TraceFlagExec (Enable exec tracing)

This attribute enables exec tracing, a subset of application tracing. The possible values are on and off. The default value is off.

TraceFlagExternal (Does CICS route system trace to an external trace facility)

CICS for AIX. This attribute specifies whether CICS routes system trace to an external trace facility. The possible values are on and off. This specification is in addition to other system-trace destinations that CICS uses. The default value is off.

TraceFlagMaster (Enables tracing for a region)

This attribute enables tracing for a region. If this attribute disables trace for the region, the value of trace flags for application and system tracing are ignored. The possible values are on and off. The default value is off.

TraceFlagSystem (Enables system tracing)

This attribute enables system tracing. The possible values are on and off. The default value is off.

TraceFlagUser (Enables user tracing)

This attribute enables user tracing, a subset of application tracing. The possible values are on and off. The default value is off.

TraceMaxSizeAux (Maximum size of the files to which CICS writes system trace entries)

This attribute specifies, in bytes, the maximum size of the files to which CICS writes system trace entries. The value can be any positive integer. The value 0 (zero) is used to indicate an unlimited size. The default value is 0.

TraceMaxSizeBuffer (Specifies size of buffer for main memory tracing)

This attribute specifies the size, in bytes, of the buffer that is used for main memory tracing. When system trace is in effect, CICS writes all system trace entries to the main memory buffer. When the buffer is full, CICS starts again at the beginning of the buffer and overwrites the previous entries. The minimum acceptable size of this buffer is 16384 bytes. The default value is 131,072.

TraceSystemSpec (Quantity of system-trace information)

This attribute determines the quantity of system-trace information to collect and the modules from which to collect it. The possible values are lists of modules and associated trace levels. The default value is all=4, which assigns trace level 0 (no collection) to all CICS modules.

TransactionRSLCheck (Type of RSL checking for Transactions)

This attribute indicates whether the region uses an External Security Manager (ESM) instead of CICS-provided resource security for transactions. The possible values are internal and external. If external is specified, the RSLCheck attribute must be set to external in the required TD entries. In addition, if external security checking is required, the ESMLoad and ESMModule attributes must be set to configure the ESM; otherwise, only internal security checking occurs. The default value is external.

TransDumpTrace (Trace buffers in transaction dump)

This attribute specifies whether the contents of the main trace buffers are included in the output of the transaction dumps that the region produces. The possible values are yes and no. The default is no.

TransientDataRSLCheck (Type of RSL checking for TDQs)

This attribute indicates whether the region uses an External Security Manager (ESM) instead of CICS-provided resource security for transient data queues. The possible values are internal and external. If external is specified, the RSLCheck attribute must be set to external in the required TD entries. In addition, if external security checking is required, the ESMLoad and ESMModule attributes must be set to configure the ESM; otherwise, only internal security checking occurs. The default value is external.

TSQAgeLimit (Expiry limit for unaccessed TSQs (days))

This attribute specifies the length of time during which TS queues can remain unaccessed before CICS purges them. The period is specified in days. The value can be between 5 and 512, or the value can be set to 0 (zero) to indicate that CICS does not perform this purge function. The default value is 20.

XAResilient

This attribute enable or disable XA resiliency. The possible values are yes and no. The default value is yes.

With the attribute value set as yes, TXSeries region remains available even after a resource manager failure during interaction of a TXSeries region with an XA compliant resource manager (failure could be detected either during starting the region or while running the transaction). Ensure that SQL errors resulting due to unavailability of RDBMS are handled appropriately in the application programs to avoid any data integrity issues.
With attribute value as no, TXSeries region will shut down after a resource manager failure during interaction of a TXSeries region with an XA compliant resource manager.

XPRecvTimeout (Timeout in seconds on ComSU_XPRecv calls)

This attribute specifies the interval in seconds that CICS waits before timing out ComSU_XPRecv calls. The value can be set from 0 (zero) to the value that is specified by the constant INT_MAX. (The value of INT_MAX is system dependent. For 32-bit systems, the value is 2147483647 seconds.) The default value is 0 (zero), meaning that the region waits for a callback indefinitely.

Note:

Do not change this setting unless you are using IBM CICS Transaction Gateway on any platform in a version earlier than 2.0.2, and CICS application server (cicsas) processes are being suspended as a result of a remote transaction abending. Setting this value to greater than 0 (zero) seconds can cause transactions that run for long periods of time (such as CEMT) to time out before completing.
If a value is set for the Timeout attribute in the Transaction Definitions (TD), that value overrides the value that is set for the XPRecvTimeout RD attribute.
XPRecvTimeout attribute has no effect if CICS Transaction Gateway client is used.