Parallel Sysplex

Considerations

Coupling Facility Level (CFLEVEL) Considerations

To support migration from one coupling facility level to the next, you can run different levels of the coupling facility concurrently as long as the coupling facility LPs are running on different CPCs. CF LPs running on the same CPC share the same coupling facility control code EC level. A single CPC cannot support multiple coupling facility levels.

CPC Support for Coupling Facility Code Levels

Coupling Facility Code Planning Considerations for CFLEVEL Migrations

ATTENTION:

When migrating cf levels, lock, list and cache structure sizes might need to be increased to support new function. for example, when you upgrade from cfcc level 14 to level 15 the required size of the structure might increase.

This adjustment can have an impact when the system allocates structures or copies structures from one coupling facility to another at different cf levels.

The coupling facility structure sizer tool can size structures for you and takes into account the amount of space needed for the current cfcc levels.

(Access the tool at: http://www.ibm.com/servers/eserver/zseries/cfsizer/)

The following table summarizes CPC support for the different coupling facility code levels.

Coupling facility code level

CPC Levels	Level 18	Level 17	Level 16	Level 15	Level 14	Level 13
2827 zEC12	EC H09167	NA	NA	NA	NA	NA
2818 z114	NA	EC N48162 (Ver 2.11.1) MCL 012	NA	NA	NA	NA
2817 z196	NA	EC N48162 (Ver 2.11.1) MCL 012	NA	NA	NA	NA
2098 z10 BC	NA	NA	EC N24403 (Ver 2.10.2) MCL 011	EC F85900 (Ver 2.10.0) MCL 006	NA	NA
2097 z10 EC	NA	NA	EC N24403 (Ver 2.10.2) MCL 011	EC F85900 (Ver 2.10.0) MCL 006	NA	NA
2096 z9 BC	NA	NA	NA	EC G409533 (Ver 2.9.2) MCL 015	EC J99670 (Ver 2.9.1) MCL 008	NA
2094 z9 EC	NA	NA	NA	EC G409533 (Ver 2.9.2) MCL 015	EC J99670 (Ver 2.9.1) MCL 008	NA

Notes

1. The EC number refers to the SE D partition EC number.

2. All MCLs cited in the table are current as of the publication date of this edition and can be superseded by later MCLs. For the latest EC and MCL information, use IBM Service Link to view the appropriate PSP bucket subset ID for hardware and software maintenance information.

3. Table updated October, 2007.

Software Corequisites

For a list of the software levels that exploit the new function and levels that can coexist with each CF level, please see the Summary of CFLEVEL Functions in the latest copy of the "PR/SM Planning Guide" on IBM ResourceLink, and the "z/OS MVS Setting Up a Sysplex" reference guide available here.

Level 18 Coupling Facility

A level 18 coupling facility (CFLEVEL=18) provides the following enhancements:
Serviceability enhancements with more triggers for non-disruptive dumps, additional structure control information in the CF dumps, and enhanced CFCC tracing support
Performance enhancements for dynamic structure size alters and DB2 GBP management

Level 17 Coupling Facility

A level 17 coupling facility (CFLEVEL=17) provides the following enhancements:

• Up to 2047 structures
• Up to 247 connectors to a lock structure, 127 connectors to a serialized list structure, and 255 connectors to an unserialized list structure. Previously there was a maximum of 32 connectors
• Non-disruptive dumps of CF data

Level 16 Coupling Facility

A level 16 coupling facility (CFLEVEL=16) provides the following enhancements:

• Improved service time for CF duplexing
• List notification improvements for IMS and MQ shared
• Increasing the structure increment size from 512 KB to 1 MB

Level 15 Coupling Facility

A level 15 coupling facility (CFLEVEL=15) provides the following enhancements:

• Increasing the allowable tasks in the Coupling Facility (CF) from 48 to 112.
• RMF Measurement Improvements

Note: When migrating CF levels, lock, list, and cache structure sizes may need to be increased to support the new function. This adjustment can impact the system when it allocates structures or copies structures from one coupling facility to another at different CF levels. The coupling facility structure sizer tool is designed to size structures for you, and takes into account the amount of space needed for the current CFCC levels.

Level 14 Coupling Facility

A level 14 coupling facility (CFLEVEL=14) provides the following enhancements:

• CFCC Dispatcher Enhancements

Our testing showed an insignificant increase in structure sizes with a CF LEVEL 14 migration

Level 13 Coupling Facility

A level 13 coupling facility (CFLEVEL=13) provides the following enhancements:

• Performance enhancements for DB2 castout processing

Level 12 Coupling Facility

A level 12 coupling facility (CFLEVEL=12) provides the following enhancements:

• 64 bit Support, removal of the 2G line
• 48 Concurrent Tasks
• Support for Message Time Ordering providing enhaced Sysplex Timer Connectivity
• System-Managed Coupling Facility Structure Duplexing
• DB2 Performance Enhancements
• Support for >15 LPARS
• Support for MCSS

Level 11 Coupling Facility

A level 11 coupling facility (CFLEVEL=11) provides the following enhancements:

• System-Managed Coupling Facility Structure Duplexing
• Support for >15 LPARS

Level 10 Coupling Facility

A level 10 coupling facility (CFLEVEL=10) provides the following enhancements:

• z900 GA2 Support

Level 9 Coupling Facility

A level 9 coupling facility (CFLEVEL=9) provides the following enhancements:

• Support for Workload Manager (WLM) Multisystem Enclaves. This provides the ability to manage and report on parallel work requests that are executed on multiple OS/390 images.
• XES Coupling Facility (CF) List Structure Architecture Extentions [also known as Message and Queuing (MQ) Series].

Level 8 Coupling Facility

A level 8 coupling facility provides the following enhancements:

• A level 8 coupling facility (CFLEVEL=8) provides a system-managed rebuild capability for list and cache structures whose users do not support user-managed rebuild, with the object of moving a structure's contents from one structure instance to another as quickly as possible. Also, two new commands -- "compute list-structure parameters" and "compute cache-structure parameters" -- have been added to replace the coupling-facility storage-allocation formulas.

Level 7 Coupling Facility

A level 7 coupling facility provides the following enhancements:

• Improves the processing efficiency of the cache structure DELETE_NAME command in cases where the name mask used to select names for deletion is equal to a pre-defined name class mask that was established when the structure was allocated. DB2 will be exploiting the enhancement.

Level 6 Coupling Facility

A level 6 coupling facility provides the following enhancements:

• TPF record level locking in the coupling facility. This enhancement provides an option to traditional locking mechanisms within DASD control units.

Level 5 Coupling Facility

A level 5 coupling facility provides the following enhancements.

• DB2 duplexing of a cache structure
• IXLCACHE request types that support version number support, enhanced castout class statistics, optional registration of interest in a data entry, and deletion of selective types of data from an entry
• IXLCACHE REQUEST=DELETE_NAMELIST command for deleting a set of data entries from a structure
• Support for cache structures containing user data field (UDF) order queues

Level 4 Coupling Facility

A level 4 coupling facility (CFLEVEL=4) provides dynamic coupling facility dispatching. Additionally, a level 4 coupling facility provides the following enhancements:

• Support for VM/ESA guest coupling simulation
• Alter and dumping support for structures containing event monitor controls (EMCs)
• IXLCACHE support enhancements:
• Support for cache write with no data
• New request type for optimized unlock of single castout lock (UNLOCK_CO_NAME)
• Lock table cleanup performance enhancements

Level 3 Coupling Facility

A level 3 coupling facility (CFLEVEL=3) provides list monitoring enhancements accessible through XES. New IXLLIST parameters provide the ability to monitor the use of keyed list structures at a finer level of granularity than previously available in the base list monitoring support. Additionally, with LIC updates, a level 3 coupling facility supports S/390 high performance coupling facility channels (HiPerLinks).

Level 2 Coupling Facility

A level 2 coupling facility (CFLEVEL=2) provides new cache and lock structure functions:

Cache structure enhancements

A cache structure user can now:

• Specify a list of data items to be registered in a single coupling facility operation.
• Write data to the cache structure conditionally, if and only if the data item is currently registered to the user with a particular specified local cache vector index.

Lock structure enhancements

• A lock structure user (lock structures are a type of list structure) can now request that a list of lock entries be released in one operation, rather than as individual operations.

Level 1 Coupling Facility

A level 1 coupling facility (CFLEVEL=1) provides the following enhancements:

Dynamic reconfiguration of coupling facility structures

Dynamic reconfiguration of coupling facility structures, also called structure alteration, provides improved availability by allowing allocated cache, list, and lock structures in a coupling facility LP to:

• Dynamically expand or contract without requiring MVS to deallocate the structure first.
• Dynamically reapportion the ratio of entries to elements for a structure while the structure remains allocated. This allows for dynamic tuning of structures providing more effective use of coupling facility LP storage resources.
• Subsystems can now specify optional IXLCONN macro keywords that:
• Allow or disallow structure alteration (ALLOWALTER=NO is the default)
• Allow or disallow structure reapportionment (RATIO=YES is the default) if structure alteration is allowed
• Set minimum percentages of entries (MINENTRY) and elements (MINELEMENT) that should exist following dynamic structure reapportionment if structure alteration is allowed

A structure can expand up to the maximum storage size you specify based on structure usage and coupling facility storage availability. Use the SIZE keyword in the coupling facility resource management policy (CFRM) to specify maximum structure size. Additionally, you can optionally specify an initial structure size (new INITSIZE keyword) that is smaller than the maximum structure size.

List processing enhancements

Beginning with MVS/ESA SP 5.2, the XES IXLLIST service offers additional support for list structure processing in a level 1 coupling facility. New IXLLIST parameters provide these new functions. For more information, see the Sysplex Services Guide, GC28-1495.