
404 Large Scale and Big Data
To achieve high availability, Stormy uses a successor list replication mechanism,
as proposed in Chord [21], where every query is replicated on several nodes, and a
replication protocol takes care that every incoming event is executed by every rep-
lica. To cope with overload situations, Stormy uses two main techniques:
1. Load balancing: The decision to balance load is made locally by a node, based
on its current utilization. Each node continuously measures its resource utili-
zation of CPU, memory, network consumption, and disk space. These param-
eters form a utilization factor, which is disseminated via the goss ...