The application that owns the structure is responsible for documenting how to determine the following information.  For a more detailed description of each of the input fields, please refer to the IXLCONN macro.

To calculate the size of an OEM list structure provide the following input data:

List headers:

Use this input parameter to specify the number of lists (list headers) for the coupling facility list structure.  The number must be greater than zero.

Lock table entry count:

Use this input parameter to specify the number of lock entries for the coupling facility list structure.  If the value for the number of lock entries is not a power of 2, it is rounded upward to the nearest power of 2.  A value of zero indicates an unserialized list.

Adjunct data:

Use this input parameter to specify whether adjunct data areas are associated with each list entry in the coupling facility list structure. Each adjunct data area is 64 bytes.

ADJUNCT=NO

Indicates that there are no adjunct data areas specified for the list structure.

ADJUNCT=YES

Indicates that each list entry in the list structure has an associated adjunct data area of 64 bytes.

Adjunct data is required when using secondary keys.

Alterable:

Use this input parameter to specify whether the list structure is alterable or not alterable.

ALTERABLE=YES

The list structure can be altered.

ALTERABLE=NO

The list structure can not be altered.

Max number of list entries:

Use this input parameter to specify the maximum number of list entries, or ENTRYCOUNT.

Max number of data elements:

Use this input parameter to specify the maximum number of data elements for the structure, or ELEMENTCOUNT.

Max number of data elements per entry:

Use this input parameter to specify a value to determine the maximum number of elements for each list entry in the coupling facility list structure.  You can specify a value from 1 to 255 for MAXELEMNUM.

Reference option:

Use this input parameter to specify how to reference list entries in the coupling facility list structure.  The requestor can specify one of the following:

REFOPTION=NONE

Indicates that the list entry can be located by the list entry identifier (LEID).  The system assigns an LEID for each list entry that is in use in the coupling facility list structure.  Neither keys nor names are used to reference list entries.

REFOPTION=KEY

Indicates that the list entry can be located by a key value. When creating the entry, the requestor can assign a key value to one or more list entries on the macro.

REFOPTION=NAME

Indicates that the list entry can be located by a unique name. When creating the entry, the requestor can assign a unique name to each list entry on the list services macro.

Key type:

Use this input parameter to specify whether only entry keys, or both entry keys and secondary keys may be used when processing or locating list entries, or when comparing the entry keys of list entries.

KEYTYPE=ENTRY

Only entry keys may be used when processing or locating list entries, or when comparing the entry keys of list entries.
Each list entry is assigned a 16-byte entry key when it is created.

KEYTYPE=SECONDARY

Both entry keys and secondary keys may be used when processing or locating list entries, or when comparing the entry keys of list entries.  Entry keys are stored in the list entry, whereas secondary keys are stored in the first 32 bytes of the 64-byte list entry adjunct area.  Note that the list structure must be allocated to use list entries with adjunct data.  Thus, in addition to KEYTYPE=SECONDARY, ADJUNCT=YES must also be specified on the IXLCONN invocation.

Max number of EMCs:

Use this input parameter to specify the maximum number of event monitor controls or EMCCOUNT.  The structure must be a keyed list structure (REFOPTION=KEY).

Data element size descriptor:

Use this input parameter to specify either an element characteristic (ELEMCHAR), an element increment number (ELEMINCRNUM), or NONE for element size determination.

Data element size value:

Use this input parameter to specify a size value for the size descriptors ELEMCHAR or ELEMINCRNUM.

DESCRIPTOR=ELEMCHAR

The element size is calculated with the formula 256*(2**ELEMCHAR), where ELEMCHAR is used as the power of 2.  For example, if ELEMCHAR=0, then the size of each element is 256 bytes.

Valid size values for ELEMCHAR range from 0 to a maximum which is based on a model-dependent limit on the size of the data elements in the coupling facility.

DESCRIPTOR=ELEMINCRNUM

The element size is calculated with the formula 256*ELEMINCRNUM.  For example, if ELEMINCRNUM=1, then the size of each element is 256 bytes.

Valid size values for ELEMINCRNUM range from 1 to a maximum which is determined by a model-dependent limit on the size of data elements in the coupling facility.  ELEMINCRNUM must be a power of 2.

If the size value is non-zero, then either ELEMCHAR or ELEMINCRNUM must be specified as the descriptor.