This paper presents M&M, a passive measurement toolkit suitable for large-scale studies of Internet path characteristics. The multiQ tool uses equally-spaced mode gaps in TCP flows’ packet interarrival time distributions to detect multiple bottleneck capacities and their relative order. Unlike previous tools, multiQ can discover up to three bottlenecks from the tcpdump trace of a single flow, a...

We present MONITORMETHOD, a tool which helps Java programmers gain insight in the behavior of their applications. MONITORMETHOD instruments the Java application and relates hardware performance monitors (HPMs) to the methods in the Java application’s source code. We present a detailed case study showing that linking microprocessorlevel performance characteristics to the source code is helpful f...

The last successful invasion of Britain began in the summer of 2004. Like all evils, it stemmed from the continent, and quickly the invaders were rumoured to be smelly, to squat in houses by the thousands and to damage the livelihood of their autochthonous relatives. The invaders go by the harmlesssounding name of Harmonia axyridis or harlequin ladybird, but there is nothing harmonious or lady-...

Although compression has been widely used for decades to reduce file sizes (thereby conserving storage capacity and network bandwidth when transferring files), there has been limited use of hardware-based compression within modern memory hierarchies of commodity systems. Why not? Especially as programs become increasingly data-intensive, the capacity and bandwidth within the memory hierarchy (i...

The increasing growth in power demand and the penetration of renewable distributed generations in competitive electricity market demands large and flexible capacity from the transmission grid to reduce transmission bottlenecks. The bottlenecks cause transmission congestion, reliability problems, restrict competition, and limit the maximum dispatch of low cost generations in the network. The ele...

Power is a big problem in data centers and a significant fraction of this power is consumed by the storage system. Server storage systems use a large number of disks to achieve high performance, which increases their power consumption. In this thesis, we explore an architecture that can significantly reduce the power consumed by the storage system via intra-disk parallelism, wherein disk drives...

Railway capacity is not only the basic condition for the allocation of railway resources but also an index set for the evaluation of the usage of them. Sometimes the maximum theoretical results calculated according to the coefficient methodology for the capacity calculation of the Existed Chinese traditional railway (abbreviated as ECTR) would be less than those statistical results from the rea...

process mining includes the automated discovery of petri nets from event logs. these event logs are the starting point for various discovery and analysis techniques of the process.  in this paper process model is developed using colored petri nets (cpns) and the supporting software package cpn tools. the restaurant process model is represented for the analysis using a combination of process min...

As home networks see increasingly faster downstream throughput speeds, a natural question is whether users are benefiting from these faster speeds or simply facing performance bottlenecks in their own home networks. In this paper, we ask whether downstream throughput bottlenecks occur more frequently in their home networks or in their access ISPs. We identify lightweight metrics that can accura...

Bottlenecks, as the key ingredients for improving the performances of the production networks, have been profoundly studied. However, the major definitions of bottlenecks are derived in terms of the throughput and based on the Theory of Constraints (TOC). Moreover, before the specific measures can be applied on them, it is not straightforward to localise dynamic bottlenecks due to their complex...