IWMECREA – Create an Enclave

The purpose of this service is to create an enclave where possibly multiple SRBs and/or TCBsmay be simultaneously executing or scheduled. For the duration of each enclave, all SRBs and TCBs associated with the enclave are treated as part of a single work request. All SRBs and/or TCBs associated with the enclave accumulate service as a single entity and are managed as a single entity. The address spaces where enclave SRBs are dispatched, as defined by the ENV= parameter of IEAMSCHD, should be non-swappable.

For more information about managing address spaces with enclaves, see Performance Management of Address Spaces with Enclaves.

For TYPE=INDEPENDENT enclaves, a new work business unit of work is created and classified according to the input Connect token's subsystem type and subsystem name, along with whatever other attributes are passed via the Classify parameter list. The current home address space is considered the owner.

For TYPE=DEPENDENT enclaves, SRM considers the enclave to be part of the current home address space's transaction, which then becomes the owning space. This space need not be connected to WLM via IWMCONN.

For TYPE=MONENV enclaves, SRM considers the enclave to be part of the address space's transaction which is delayed according to the input monitoring environment, as set when IWMMINIT or IWMMRELA was used. This space becomes the owning space. This space need not be connected to WLM via IWMCONN.

For both TYPE=MONENV and TYPE=DEPENDENT enclaves, SRM will change the enclave to TYPE=INDEPENDENT if the owning address space's transaction ends.

For both TYPE=MONENV and TYPE=DEPENDENT enclaves, SRM will check the enclave for period switch when the owning address space is swapped in. If the owning address space is swapped out SRM will continue to accumulate service for any enclaves owned by the space, but will not check the address space and any owned enclave for period switch until the address space is swapped in again. The presence of enclaves does not make the address space appear to be ready from an SRM point of view.

Enclaves are deleted if the owning address space terminates. TYPE=INDEPENDENT enclaves are deleted if the owning address space disconnects or the TCB which connected terminates.

Enclaves should only be created when this environment is ready for execution, and should not be used when prolonged queueing effects are possible prior to the scheduling of the first SRB (IEAMSCHD) or the first task join (IWMEJOIN). "Prolonged" would certainly include times measured in seconds. The service allows the caller to pass the queueing time prior to creation of the enclave so that this may be separately reported.