@conference {2018:benchflow:coopis,
	title = {Evaluating Multi-Tenant Live Migrations Effects on Performance},
	booktitle = {26th International Conference on Cooperative Information Systems (CoopIS)},
	year = {2018},
	month = {October},
	address = {Valletta, Malta},
	abstract = {Multitenancy is an important feature for all Everything as a Service providers like Business Process Management as a Service. It allows to reduce the cost of the infrastructure since multiple tenants share the same service instances. However, tenants have dynamic workloads. The resource they share may not be sufficient at some point in time. It may require Cloud resource (re-)configurations to ensure a given Quality of Service. Tenants should be migrated without stopping the service from a configuration to another to meet their needs while minimizing operational costs on the provider side. Live migrations reveal many challenges: service interruption must be minimized and the impact on co-tenants should be minimal. In this paper, we investigate live tenants migrations duration and its effects on the migrated tenants as well as the co-located ones. To do so, we propose a generic approach to measure these effects for multi-tenant Software as a Service. Further, we propose a testing framework to simulate workloads, and observe the impact of live migrations on Business Process Management Systems. The experimental results highlight the efficiency of our approach and show that migration time depends on the size of data that have to be transferred and that the effects on co-located tenants should not be neglected. },
	keywords = {BenchFlow, Multi-tenant, Performance Testing, workflow engine},
	author = {Guillaume Rosinosky and Chahrazed Labba and Vincenzo Ferme and Samir Youcef and Fran{\c c}ois Charoy and Cesare Pautasso}
}
@conference {benchflow:2016:bpm,
	title = {Estimating the Cost for Executing Business Processes in the Cloud},
	booktitle = {BPM Forum},
	year = {2016},
	month = {September},
	pages = {72--88},
	publisher = {Springer},
	organization = {Springer},
	address = {Rio de Janeiro, Brazil},
	abstract = {Managing and running business processes in the Cloud changes how Workflow Management Systems (WfMSs) are deployed. Consequently, when designing such WfMSs, there is a need of determining the sweet spot in the performance vs. resource consumption trade-off. While all Cloud providers agree on the pay-as-you-go resource consumption model, every provider uses a different cost model to gain a competitive edge. In this paper, we present a novel method for estimating the infrastructure costs of running business processes in the Cloud. The method is based on the precise measurement of the resources required to run a mix of business process in the Cloud, while accomplishing expected performance requirements. To showcase the method we use the BenchFlow framework to run experiments on a widely used open-source WfMS executing custom workload with a varying number of simulated users. The experiments are necessary to reliably measure WfMS{\textquoteright}s performance and resource consumption, which is then used to estimate the infrastructure costs of executing such workload on four different Cloud providers.},
	keywords = {BenchFlow, cloud computing, cloud workflows},
	doi = {10.1007/978-3-319-45468-9_5},
	author = {Vincenzo Ferme and Ana Ivanchikj and Cesare Pautasso}
}
