SYSSTC is the "default" service class for started tasks unless you specify
Since SMR spools the log and is continually executing to perform its task,
the classification should be adequate enough to allow it to function as
efficiently as possible.
If you assign STCHI to SMR then this can also work if your logging
intervals are not agressive. STCHI will keep SMR running properly and not
impact performance unless your system is constantly swapping out higher
rated workload assigned utilities.
CA documentation says nothing about Workload management settings. But always remain as standardized as you can based on the product purpose and scope as you would any other product that performs the same functions.
Service class STCHI or SYSSTC will usually work properly with no issues. Recommendation is SYSSTC to follow IBM's standards regarding queue related started tasks.