Coupling Facility Information

You can request information about all coupling facilities that are attached to the system on which the IXLMG macro is issued or about a specific coupling facility that is connected to the system on which IXLMG is issued. If you specify a coupling facility by name (CFNAME), the data returned includes information about all allocated structures within the coupling facility as well as the coupling facility information.

The statistics gathered from the coupling facility (requested by specifying the HWSTATISTICS=YES parameter) include structure control information and coupling facility measurement data. If you do not want this information, you must explicitly code HWSTATISTICS=NO. If you want the statistics gathered from the coupling facility to include only the coupling facility measurement data but not the structure control information, code HWSTATISTICS=CF.

Note that the number of accesses to the coupling facillity for data gathering might degrade a system's performance. If you need primarily coupling facility statistics as opposed to individual structure statistics, you should use HWSTATISTICS=CF, which will generate fewer accesses to the coupling facility than HWSTATISTICS=YES.

The coupling facility information returned includes:

If HWSTATISTICS=YES
- AMDCF and AMDCF1 include configuration data, accounting and measurement data, and control information.
- AMDSLL and AMDSLL1 (list structure limits) and AMDSLC and AMDSLC1 (cache structure limits) are returned.
- AMDSTRL and AMDSTRL1 (list structure entry) and AMDSTRC and AMDSTRC1 (cache structure entry) are returned for all structures in the coupling facility regardless of whether there's an active XES connection to that structure on this system. AMDSTRL, AMDSTRL1, AMDSTRC, and AMDSTRC1 include configuration data, measurement data, and control information for all structures.
  Structure usage information in AMDSTRL, AMDSTRL1, AMDSTRC, and AMDSTRC1 is available only for structures that have an active XES connection to that structure on this system.
- AMDSC and AMDSC1 (subchannel information) include configuration and contention data.
- AMDCFMI and AMDCFMINFO (measurement information array) includes measurement information elements.
If HWSTATISTICS=NO
- AMDCF and AMDCF1 include configuration data, accounting and measurement data, and control information.
- AMDSLL and AMDSLL1 (list structure limits) and AMDSLC and AMDSLC1 (cache structure limits) are returned.
- AMDSTRL and AMDSTRL1 (list structure entry) and AMDSTRC and AMDSTRC1 (cache structure entry) are returned only for structures that have an active XES connection to that structure on this system. AMDSTRL, AMDSTRL1, AMDSTRC, and AMDSTRC1 include configuration data and measurement data.
  AMDSTRL, AMDSTRL1, AMDSTRC, and AMDSTRC1 do not contain structure control information.
- AMDSC and AMDSC1 (subchannel information) include configuration and contention data.
- AMDCFMI and AMDCFMINFO (measurement information array) are not returned.
If HWSTATISTICS=CF
- AMDCF and AMDCF1 include configuration data, accounting and measurement data, and control information.
- AMDSLL and AMDSLL1 (list structure limits) and AMDSLC and AMDSLC1 (cache structure limits) are returned.
- AMDSTRL and AMDSTRL1 (list structure entry) and AMDSTRC and AMDSTRC1 (cache structure entry) are returned only for structures that have an active XES connection to that structure on this system. AMDSTRL, AMDSTRL1, AMDSTRC, and AMDSTRC1 include configuration data and measurement data.
  AMDSTRL, AMDSTRL1, AMDSTRC, and AMDSTRC1 do not contain structure control information.
- AMDSC and AMDSC1 (subchannel information) include configuration and contention data.
- AMDCFMI and AMDCFMINFO (measurement information array) include measurement information elements.
If HWSTATISTICS=YES or CF and AMDALEVEL=1 with CFLEVEL=10 or higher, the following information pertains to remotely connected coupling facilities:
- AMDCF and AMDCF1 includes an additional field to report the remotely connected coupling facilities for each subject CF. The remotely connected coupling facility records are chained together in a linked list in the IXLYAMDA answer area, so that information for any number of remotely connected CFs connected to a given coupling facility can be returned.
- AMDCFRF contains information about each remotely connected coupling facility:
  - Node descriptor (ND)
  - System identifier (SYID) that designates the coupling facility's ownership by a particular sysplex.
  - Coupling facility name (CFNAME) — if available, otherwise binary zeros.
  - Path group size (PGS) — the number of currently active paths (CF-to-CF links) connecting this coupling facility to the remote coupling facility.
  - CF-to-CF signal counter information. (CF-to-CF signals are those signals exchanged over the CF-to-CF links to synchronize the execution of duplexed commands in system-managed duplexing rebuild.)
  - CF-to-CF signal service time information, including sum of times and sum of squares of times for signal service times and delay times.
    Note that a remotely connected coupling facility entry for a coupling facility at CFLEVEL=10 will specify the sum of signal service times in IXLYAMDCFRF_SSTFM. For a coupling facility at CFLEVEL=11 or higher, the same information may also appear in IXLYAMDCFRF_SSTFME. For CFLEVEL=11, the SSTRM field was extended to 64-bits to prevent the value from wrapping in a given data-gathering interval. To determine which field to use, test IXLYAMDCFRF_SSTFME. If it is non-zero, use that value; otherwise obtain the value from IXLYAMDCFRF_SSTFM.
  - Chpid type information for each currently active path in the path group.