SAP Parameter vmcj/jni_strategy - define strategy for JNI methods


Short text
Define strategy for JNI methods
This parameter specifies how kernel functions implemented within the SAPkernel in C or C++ are called in the VM container. It is important thatthe VM C/C++ runtime stacks required for each thread are configured assmall as possible in order to save memory space. Depending on thefunction type, this may lead to problems (large fields on the stack,recursive functions). In the VM container there is a service stack thatis configured larger, which can execute large functions without anyproblem. The disadvantage of this service stack is a relatively smallloss in performance resulting from the need to switch stacks.
Since the switch to the service stack is only required by a fewfunctions, all kernel functions were classified that

  • can run directly on the VM stack.

  • have to run on the service stack.

  • By default, the VM container uses this information to execute functions.If there are still problems, and if it is not possible to change thesize of the stack because of the available memory, this behavior can bechanged.
    The following options are available:
    USE_MARKUP Call based on classification
    INVOKE_ON_SERVICE_STACK Always call on the service stack
    INVOKE_DIRECT Always call directly

    Work area

    Parameter unit
    Character string

    Default value

    Who is allowed

    Limitation for os

    Limitation for db

    Other parameter