Detecting and Analyzing I/O Performance Regressions

Regression testing can be done by re-executing a test suite on different software versions and comparing the outcome. For functional testing, the outcome of such tests is either pass (correct behaviour) or fail (incorrect behaviour). For non-functional testing, such as performance testing, this is more challenging as correct and incorrect are...

Performance Optimization of Multi-Tenant Software Systems

Multi-tenant software systems are Software-as-a-Service systems in which customers (or tenants) share the same resources. The key characteristics of multi-tenancy are hardware resource sharing, a high degree of configurability and a shared application and database instance. We can deduct from these characteristics that they lead to challenges...

Using Pattern Recognition Techniques for Server Overload Detection

One of the key factors in customer satisfaction is application performance. To be able to guarantee good performance, it is necessary to take appropriate measures before a server overload occurs. While in small systems it is usually possible to predict server overload using a subjective human expert, an automated overload prediction mechanism is...

Server Overload Detection and Prediction Using Pattern Classification

One of the key factors in customer satisfaction is the application performance. In traditional settings, it is usually not very difficult to manually detect a performance problem, however, with the advent of ultra-large-scale (ULS) systems [4], manual performance monitoring and prediction becomes tedious and would thus ideally require automation...

Enabling multi-tenancy: An industrial experience report

Multi-tenancy is a relatively new software architecture principle in the realm of the Software as a Service (SaaS) business model. It allows to make full use of the economy of scale, as multiple customers – “tenants” – share the same application and database instance. All the while, the tenants enjoy a highly configurable application, making it...

Challenges of reengineering into multi-tenant SaaS applications

Multi-tenancy is a relatively new software architecture principle in the realm of the Software as a Service (SaaS) business model. It allows to make full use of the economy of scale, as multiple customers "tenants" share the same application and database instance. All the while, the tenants enjoy a highly configurable application, making it...

The MAC framework: Redefining MAC protocols for wireless sensor networks

Most current WSN MAC protocol implementations have multiple tasks to perform—deciding on correct timing, sending of packets, sending of acknowledgements, etc. However, as much of this is common to all MAC protocols, there is duplication of functionality, which leads to larger MAC protocol code size and therefore increasing numbers of bugs....