Studien avsåg att olika aspekter för att skapa underlag för utvecklingen med att förbättra fleranvändning. Syftet var, utöver de olika aspekterna, att på konceptuell nivå utvärdera hur fleranvändning kan utföras tekniskt samt undersöka hur användarna påverkas av denna förändring. Detta har utförts genom flertalet workshops och intervjuer. Vid två tillfällen har också författarna till rapporten utbildats i hur systemet är uppbyggt och hur det används. Utifrån detta har värdekriterier värderats mot olika tekniker. De teknikerna är Mutex, Semaphores och Oracle Tuxedo. På det sättet har olika aspekter beaktats och konceptuella modeller har målats upp. De olika teknikerna lever alla upp till de tekniska kraven som ställts, som programmeringsspråket C# och en databas från Oracle. I samverkan mellan användare och utvecklare har nivån på lösningen tagits fram, vad den ger användarna för nytta samtidigt som det inte är för komplicerat. Dessutom har det ställts krav angående prestandan, att den inte får försämras väsentligt. Användarna får ett liknande arbetssätt med minskade krav på samordning. Det medför att de kan samarbeta med de datamängder de behöver. Den lösning som passade bäst utifrån dessa kriterier var Mutex. / This paper is intended to study different aspects and take them in consideration to create a foundation for the developers to improve a multi-user environment. The purpose was to evaluate how to develop multi-user systems at a conceptual level with the technical aspects and describe how the users were affected by this. The study is based on multiple workshops and interviews. The writers have also been educated on how the system is used by the users and how the system was built, at two separate occasions. Based on this, criterias were made and these were valued against different techniques. These techniques are Mutex, Semaphores and Oracle Tuxedo. The criterias were considered and conceptual models were made to visualize the solution. The different techniques all live up to the constraints from the hardware and software of the case study, like the programming language C# and a database from Oracle. In a cooperation between the developers and users have the level of the solution been defined, where the solution ease the problems enough and still not too complex to implement. There have also been a few directions on the performance of the system. The solution should not be affecting the performance significantly. The users’working methods are not going to be particularly affected. The main part of the cooperation are not as needed as before. They can work in the same dataset concurrent in the datasets they required. On this basis the best technique to use in this case was Mutex.

Technology improvements and power constrains have taken multicore architectures to dominate microprocessor designs over uniprocessors. At the same time, accelerator based architectures have shown that heterogeneous multicores are very efficient and can provide high throughput for parallel applications, but with a high-programming effort. We propose Castell a scalable chip multiprocessor architecture that can be programmed as uniprocessors, and provides the high throughput of accelerator-based architectures. Castell relies on task-based programming models that simplify software development. These models use a runtime system that dynamically finds, schedules, and adds hardware-specific features to parallel tasks. One of these features is DMA transfers to overlap computation and data movement, which is known as double buffering. This feature allows applications on Castell to tolerate large memory latencies and lets us design the memory system focusing on memory bandwidth. In addition to provide programmability and the design of the memory system, we have used a hierarchical NoC and added a synchronization module. The NoC design distributes memory traffic efficiently to allow the architecture to scale. The synchronization module is a consequence of the large performance degradation of application for large synchronization latencies. Castell is mainly an architecture framework that enables the definition of domain-specific implementations, fine-tuned to a particular problem or application. So far, Castell has been successfully used to propose heterogeneous multicore architectures for scientific kernels, video decoding (using H.264), and protein sequence alignment (using Smith-Waterman and clustalW). It has also been used to explore a number of architecture optimizations such as enhanced DMA controllers, and architecture support for task-based programming models. iii

Tato práce rozšiřuje nástroj ANaConDA pro dynamickou analýzu vícevláknových programů o možnost analyzovat také programy víceprocesové. Část práce se soustředí na popis nástroje ANaConDA a mechanismů, které pro monitorování využívá, a na jejich nutné úpravy vzhledem k rozdílům procesů a vláken. Tyto zahrnují nutnost složitějších mechanismů pro meziprocesovou komunikaci, nutnost překládat logické adresy na jiný jednoznačný identifikátor a monitorování obecných semaforů. Rozšíření pro monitorování procesů tyto problémy řeší za vývojáře analyzátorů, čímž velmi zjednodušuje jejich vývoj. Užitečnost rozšíření je ukázána na implementaci dvou analyzátorů pro detekci souběhu (AtomRace a FastTrack), které bylo dosud možné využít pouze na vícevláknové programy. Implementace algoritmu FastTrack využívá happens-before relaci pro obecné semafory, která byla také definována jako součást této práce. Experimenty s analyzátory na studentských projektech ukázaly, že nástroj ANaConDA je nyní schopen detekovat paralelní chyby i ve víceprocesových programech a může tak pomoci při vývoji další skupiny paralelních programů.