Tcep

Abstract

Operator placement has a profound impact on the performance of a distributed complex event processing system (DCEP). Since the behavior of a placement mechanism strongly depends on its environment; a single placement mechanism is often not enough to ful ll stringent performance requirements under environmental changes. In this paper, we show how DCEP can bene t from the adaptive use of multiple placement mechanisms. We propose T , a DCEP system to integrate multiple placement mechanisms. By enabling transitions, T can seamlessly exchange distinct operator mechanisms at runtime. We make two main contributions that are highly important for a cost-e cient transition: i) a transition strategy for e ciently scheduling state migrations and ii) a lightweight learning algorithm to adaptively select an appropriate placement mechanism as a consequence of a transition. Our evaluations for important decentralized placement mechanisms in the context of an IoT scenario show that transitions can better ful ll QoS demands in a dynamic environment. Thereby, e cient scheduling of state migrations can help to faster complete transitions by up to 94 %. CCS CONCEPTS• Computer systems organization → Distributed architectures; • Networks → Network dynamics;