Multiple instance subprocess : limite concurent


i have a BPMN like that:

<subProcess id="sid-subProcess_1" flowable:async="true" flowable:exclusive="false">
        <multiInstanceLoopCharacteristics isSequential="false" flowable:collection="myCollection" flowable:elementVariable="myVariable"/>
        <serviceTask id="sid-TASK1" flowable:exclusive="false" flowable:delegateExpression="${myDelegate}">

myCollection can have hundred thousands of elements.
I need to limit the maximum number of concurent executions of this subprocess.

How can i do that? (or is there another solution to this problem?)