DB2 for z/OS, Distributed Workload, and Enclaves

If you work with DB2 for z/OS and have to manage distributed workload… or if you are enabling zIIP specialty processors… chances are you’ve at least heard the term “enclave” or “enclave SRB” before. But do you understand what an enclave is and why it is important?

An enclave is a construct that represents a transaction or unit of work. Enclaves are a method of managing mainframe transactions for non-traditional workloads. You can think of an enclave as an anchor point for resource accumulation regardless of where the transaction is executing.

With traditional workloads it is relatively easy to map the resources consumed to the actual transaction doing the consumption. But with non-traditional workloads – web transactions, distributed processing, etc. – it is more difficult because the transaction can span platforms. Enclaves are used to overcome this difficulty by correlating closely to the end user’s view of the transaction. 

An enclave can consist of many pieces spread over many server address spaces. So even though a non-traditional transaction can comprise multiple “pieces” spanning many address spaces, and can share those address spaces with other transactions, an enclave gives you control over the non-traditional workload. And WLM can be used to more effectively manage non-traditional workload via the enclave.

If you are interested in more details on enclaves and how they are managed, read through Enclaves – Managing Business Transactions from IBM’s RMF Newsletter.