Modern computer hardware platforms are moving towards high core-count and heterogeneous Instruction Set Architecture (ISA) processors to achieve improved performance as single core performance has reached its performance limit. These trends put the current monolithic SMP operating system (OS) under scrutiny in terms of scalability and portability. Proper pairing of computing workloads with computing resources has become increasingly arduous with traditional software architecture. One of the most promising emerging operating system architectures is the Multi-kernel. Multi-kernels not only address scalability issues, but also inherently support heterogeneity. Furthermore, provide an easy way to properly map computing workloads to the correct type of processing resources in presence of heterogeneity. Multi-kernels do so by partitioning the resources and running independent kernel instances and co-operating amongst themselves to present a unified view of the system to the application. Popcorn is one the most prominent multi-kernels today, which is unique in the sense that it runs multiple Linux instances on different cores or group of cores, and provides a unified view of the system i.e., Single System Image (SSI). This thesis presents four contributions. First, it introduces a filesystem for Popcorn, which is a vital part to provide a SSI. Popcorn supports thread/process migration that requires migration of file descriptors which is not provided by traditional filesystems as well as popular distributed file systems, this work proposes a scalable messaging based file descriptor migration and consistency protocol for Popcorn. Second, multi-kernel OSs rely heavily on a fast low latency messaging layer to be scalable. Messaging is even more important in heterogeneous systems where different types of cores are on different islands with no shared memory. Thus, another contribution proposes a fast-low latency messaging layer to enable communication among heterogeneous processor islands for Heterogeneous Popcorn. With advances in networking technology, newest Ethernet technologies are able to support up to 40 Gbps bandwidth, but due to scalability issues in monolithic kernels, the number of connections served per second does not scale with this increase in speed.Therefore, the third and fourth contributions try to address this problem with Snap Bean, a virtual network device and Angel, an opportunistic load balancer for Popcorn's network system. With the messaging layer Popcorn gets over 30% performance benefit over OpenCL and Intel Offloading technique (LEO). And with NetPopcorn we achieve over 7 to 8 times better performance over vanilla Linux and 2 to 5 times over state-of-the-art Affinity Accept. / Master of Science

This thesis describes preparation for porting as well aw porting itself of RedirFS Linux kernel module to FreeBSD. Basic differences between Linux and FreeBSD kernels are described as well as differences in implementation of the Virtual Filesystem, crucial part for RedirFS. Further there are described possibilities and different approaches to implementation RedirFS functionality to FreeBSD. Then, the possibilities are evaluated and ideal approach is proposed. Next chapters introduces required functionality of the new module as well as its solutions. Then the implementation details are described so the reader can very well understand how the new module works and how the required functionality is implemented into the module.

Ziel der Arbeit war es, eine Client-Server-basierte Loesung zu entwickeln, welche eine Backupfunktionalitaet in einer heterogenen Workstationumgebung mit dezentralen Filesystemen bereitstellt. Das System sollte mit Hilfe einer Scriptsprache implemetiert werden, um die Systemunabhaengigkeit der Komponenten zu gewaehrleisten. Zu diesem Zwecke wurde als Grundlage das ¨Remote Scripting Environment¨, welches Gegenstand der Diplomarbeit von Andre Glaesz am Lehrstuhl Betriebssysteme war, gewaehlt.

Logical Volume Management, auf kommerziellen UNIX-System (z.B. AIX, HP-UX) schon seit Jahren im Einsatz, ist mittlerweile auch fuer Linux verfuegbar. Der Vortrag bietet eine Einfuehrung in LVM unter Linux, einen Ueberblick ueber die aktuelle LVM-Technologie auf Linux sowie deren Einsatz.

Unterlagen zu einem Workshop im Rahmen des 4. Chemnitzer Linux Tages. Es wird die Installation von AFS-Servern und -Klienten demonstriert. Dabei werden wichtige Eigenschaften gezeigt und einige typische Administrations-Aufgaben erläutert.

Flexible Verwaltung von Plattenkapazität, Umbauten an Volumes zur Laufzeit, konsistente Backups aus dem laufenden Betrieb - LVM.

Nowadays there is wide variety of programming languages and platforms providing com-plex set of tools for software development -- from mobile and desktop applications up to server applications. Java is one of the most popular choices for software project develop-ment since many years. Many changes and improvements of the Java language occurred throughout 23 years of development of the platform. Current version brings many changes description of whom is considered to be beneficial not only for developers but also for the community around Java platform. This thesis covers the changes that were introduced in the release of Java 7. The thesis lists the short review of main historical events that happened since the beginning of the platform and analyses changes in libraries as well as describes syntactical changes. Primary focus is placed on the NIO (New I/O) library, whose current name is Non-Blocking I/O (NIO.2). Even though massive changes had occurred in this library, not many people actually noticed anything. This unfortunate situation is now described as a quiet revolution. Last but not least a description of changes in other libraries and Java Virtual Machine is presented.

This term project describes the concept of information system based on the virtual file system and the reasons which led to the creation of this concept. It discusses the basic approaches to solve common parts of the functionality of information system (such as access rights management, structure of data and managing configuration of system) and tries to find the concept that solves this functionality consistently and easily. The main objective of the proposed concept is to create a system that brings simplicity and intuitiveness of user interface, unification of common functionality and maximum flexibility and extensibility. The whole concept is based on the representation of the system as a tree of virtual files on which user performs actions.

Ziel der Arbeit war es, eine Client-Server-basierte Loesung zu entwickeln, welche eine Backupfunktionalitaet in einer heterogenen Workstationumgebung mit dezentralen Filesystemen bereitstellt. Das System sollte mit Hilfe einer Scriptsprache implemetiert werden, um die Systemunabhaengigkeit der Komponenten zu gewaehrleisten. Zu diesem Zwecke wurde als Grundlage das ¨Remote Scripting Environment¨, welches Gegenstand der Diplomarbeit von Andre Glaesz am Lehrstuhl Betriebssysteme war, gewaehlt.

Logical Volume Management, auf kommerziellen UNIX-System (z.B. AIX, HP-UX) schon seit Jahren im Einsatz, ist mittlerweile auch fuer Linux verfuegbar. Der Vortrag bietet eine Einfuehrung in LVM unter Linux, einen Ueberblick ueber die aktuelle LVM-Technologie auf Linux sowie deren Einsatz.