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Instrumentation and Evaluation for Dynamic Program Analysis
Marek, Lukáš ; Tůma, Petr (advisor) ; Hasselbring, Wilhelm (referee) ; Krall, Andreas (referee)
A dynamic program analysis provides essential information during later phases of an application development. It helps with debugging, profiling, performance optimizations or vulnerability detection. Despite that, support for creating custom dynamic analysis tools, especially in the domain of managed languages, is rather limited. In this thesis, we present two systems to help improve application observability on the Java platform. DiSL is a language accompanied with a framework allowing simple and flexible instrumentation for the dynamic program analysis. DiSL provides high level abstractions to enable quick prototyping even for programmers not possessing a knowledge of Java internals. A skilled analysis developer gains full control over the instrumentation process, thus does not have to worry about unwanted allocations or hidden execution overhead. ShadowVM is a platform that provides isolation between the observed application and the analysis environment. To reduce the amount of possible interactions between the analysis and the application, ShadowVM offloads analysis events out of the context of the application. Even though the isolation is the primary focus of the platform, ShadowVM introduces a number of techniques to stay performance comparable and provide a similar programming model as existing...
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Run-time performance testing in Java
Kotrč, Jaroslav ; Horký, Vojtěch (advisor) ; Tůma, Petr (referee)
This work focuses on relative comparisons of individual methods performance. It is based on Stochastic Performance Logic, which allows to express, for example, that one method runs at most two times longer than another method. This results are more portable than absolute values. It extends standard unit tests with performance assumptions, which are evaluated during actual run-time of a released application. Dynamically added and removed instrumentation is used for automatic modification of the production code. Instrumentation part uses DiSL framework to be able to seamlessly measure even Java system classes. Methods are measured sequentially, number of concurrently measured method is dynamically changed and measurement code is removed as soon as required data are obtained to avoid high overhead. The results show that for processor demanding application this approach may bring up to 3-times lower overhead peaks than measuring all methods at once. Powered by TCPDF (www.tcpdf.org)
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Deployment of Performance Evaluation Tools in Industrial Use Case
Täuber, Jiří ; Tůma, Petr (advisor) ; Šimko, Viliam (referee)
Nowadays software performance is evaluated not only by specialized review companies but it is more and more starting to be a common practice for the software developers themselves. Companies are often forced to develop and maintain their own tools for measuring performance of the developed applications. On the Faculty of Mathematics and Physics there has been created a toolkit for automation of software performance evaluation called BEEN. This toolkit should significantly ease the management of individual performance measurements but it is not possible to test it thoroughly in the environment where it was created. The goal of this thesis is to deploy BEEN in a real environment of commercially oriented company and evaluate the usability of this toolkit for the developers. We will focus on evaluating both objective and subjective positives and drawbacks of this toolkit as observed by unbiased users.
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IPv6 for HelenOS
Steinhauser, Antonín ; Děcký, Martin (advisor) ; Tůma, Petr (referee)
This thesis extends HelenOS operating system in order to be IPv6 capa- ble. New IPv6 protocol implementation is on the same level as previous IPv4 protocol implementation. HelenOS networking stack now offers three modes of networking: IPv4-only, IPv6-only and dual stack mode. Dual stack mode enables usage of both protocols at once. The thesis describes previous state of HelenOS networking stack, analyzes differences between IPv4 and IPv6 protocols and gives reasons for single strategic decisions. In fine, it describes used implementation and debugging techniques, concludes results and compares HelenOS with other microkernel operating system from the IPv6-capability perspective. 1
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Capturing Performance Assumptions using Stochastic Performance Logic
Trojánek, Tomáš ; Tůma, Petr (advisor) ; Bednárek, David (referee)
Performance testing is a mean used to evaluate speed of software projects. In an ideal state a project has a set of tests attached to it and such set may be repeat- edly executed in order to verify that all performance expectations are satisfied. The most widespread method of constructing these tests nowadays is based on measuring absolute time values. A test executes a chosen application unit and then compares the time it took to complete with a precise bound, which has been determined in advance. However, this approach has several disadvantages that affect reliability of such tests. First of all, the way in which those precise bounds should be established is not clear. And even if it is, then the bounds are tied to a certain hardware configuration. As a remedy, this thesis demonstrates a whole another approach, which is based on relative performance comparison. Using a logic built on top of a research published by the issuing department, chosen application units are compared together in a manner that makes results of such tests more reliable even to a change of hardware configuration. The presented theory is also implemented and verified on selected use cases. 1
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Determination of Lithium in Mineral Waters Using Electrophoresis in Short Capillary.
Makrlíková, Anna ; Opekar, František (advisor) ; Tůma, Petr (referee)
The aim of this study was determination of lithium ion concentration in mineral waters "Vincentka" and "Bílinská kyselka" using capillary electrophoresis with contactless conductivity detection. A specialized laboratory-made apparatus designed for separations in short capillaries was first tested for separation of model solution of common inorganic cations and then for analysis of mineral water samples. Lithium ion concentration was determined using method of standard addition. The results obtained were compared with those obtained from atomic absorption and emission spectroscopy; standard addition method as well as the method of calibration graph were used in spectroscopic methods. A good agreement was obtained between experimentally determined concentrations of lithium and those declared in the labels on the mineral water bottles. Keywords Capillary electrophoresis, contactless conductivity detection, mineral waters, lithium, atomic absorption spectroscopy, atomic emission spectroscopy
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Portability in zlomekFS
Šnupárek, Aleš ; Tůma, Petr (advisor) ; Yaghob, Jakub (referee)
ZlomekFS is a distributed file system created for transparent sharing of directory trees designed for the Linux operating system. This work deals with the possibility of zlomekFS portability to another operating system especially the Microsoft Windows. It also explores the possibility of porting zlomkeFS to the Android operating system.
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HelenOS port to Xen hypervisor
Benhák, Tomáš ; Děcký, Martin (advisor) ; Tůma, Petr (referee)
The goal of the master thesis is the paravirtualization of HelenOS operating system for Xen hypervisor on IA-32. The result of the thesis is a prototype implementation which allows to run HelenOS as a PV guest under Xen hypervisor. The thesis analyses the Xen hypervisor interface with respect to the paravirtualized operating system running under it, the relevant parts of HelenOS kernel and changes in them forced by the paravirtualization.
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