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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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Improving Accuracy of Software Performance Models on Multicore Platforms with Shared Caches
Babka, Vlastimil ; Tůma, Petr (advisor) ; Eeckhout, Lieven (referee) ; Black-Schaffer, David (referee)
The context of this work are performance models of software systems, which are used for predicting performance of a system in its design phase. For this purpose, performance models capture the explicit interactions of software components that make up the system, and the resource demands of primitive actions performed by the components. On contemporary hardware platforms, the software components however interact also through implicit sharing of numerous resources such as processor caches, which influence the performance of the primitive actions. Implicit resource sharing is often omitted in performance models, which affects their prediction accuracy. In this work we introduce two methods for including resource sharing models in performance models. Next, we propose an approximate resource sharing model based on linear regression, and a detailed model for predicting performance impact of cache sharing. The cache model is validated on a real processor and its design is preceded by extensive experiments which investigate the performance aspects of cache sharing. In addition, we introduce a method for robust validation of performance models using many automatically generated applications.
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Applications of capillary electrophoresis in life sciences
Křížek, Tomáš ; Coufal, Pavel (advisor) ; Pacáková, Věra (referee) ; Tůma, Petr (referee)
Tomáš Křížek: Applications of Capillary Electrophoresis in Life Sciences (Dissertation thesis) ABSTRACT This thesis is focused on the applications of capillary electrophoresis in two important areas of life sciences, proteomics and enzyme assays. In the first part, Pluronic F-127 copolymer was studied as a sieving matrix for proteomic applications of capillary gel electrophoresis. The effect of thermoassociation of Pluronic F-127 on the separation selectivity was investigated and no difference in selectivity of the separation below, inside and above the thermoassociation temperature region was observed. The performance of Pluronic F-127 in capillary gel electrophoresis was compared with dextran as a commonly used sieving matrix. The results showed, that Pluronic F-127 offers superior performance for low-molecular-mass proteins because it provides higher separation power than dextran with significantly lower viscosity of the background electrolyte. The lower viscosity makes the polymer easier to replace after each analysis, which leads to remarkably higher repeatability of the experiments. On the other hand, dextran, due to its higher viscosity, was shown to be more convenient for separations of protein digests, where extremely high separation efficiency is required. The second part focuses on...
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Portability in zlomekFS
Šnupárek, Aleš ; Tůma, Petr (advisor) ; Ježek, Pavel (referee)
ZlomekFS is a distributed file system designed for transparent sharing of directory trees. This work deals with the possibility of portability zlomekFS to another operating system. The first section describes the problems that must be solved in order to achieve portability of the program. Subsequently, this work examines the possibility of deploying this file system on the Android operating system. Furthermore, this work deals with porting zlomekFS to the Windows operating system. The last section defines general guidelines for the file system code portability.
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The use of a capillary electrophoresis and capillary electrophoresis on chip for clinical research
Pavlíček, Václav ; Tůma, Petr (advisor) ; Pacáková, Věra (referee) ; Dlouhý, Pavel (referee)
Present the dissertation thesis on the topic "The use of a capillary electrophoresis and electrophoresis on chip for clinical research" is divided into two separate parts. The first chapter summarizes the problems of development new method of very rapid determination of uric acid and creatinine using capillary electrophoresis in human urine and serum, when the entirely original solution has been developed for implementation of very fast electrophoretic separations in a commercial electrophoretic apparatus. The separations were performed in a laboratory made capillary formed by connecting a 9.7 cm long separation capillary with inner diameter (d) 25 µm with an auxiliary 22.9 cm long capillary with d 100 µm. The coupled capillary is characterized by the effective separation path 8.3 cm (short-end injection mode) and the high electric field intensity around 2.3 kV per cm. The coupled capillary was tested at several high-speed analysis; i) the determination of creatinine in human urine, background electrolyte - 20 mM citric acid/NaOH, pH 3.0; ii) the determination of uric acid in human urine, background electrolyte - 20 mM MES/NaOH, pH 6.0. Under these experimental conditions, migration times of 12.2 s for creatinine and 8.6 s for uric acid were achieved and the attained separation efficiency was...
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HelenOS Monitoring
Kozina, Stanislav ; Děcký, Martin (advisor) ; Tůma, Petr (referee)
The main purpose of an operating system is to supply the user programs with persistent, simple and enough powerful service interface. However for practical use of the system it is often necessary to know the current state of the system, how much resources the system is using and which user programs consume the biggest portion of them. In the thesis we discuss the possibilities of the operating system monitoring in common. For HelenOS system (which was missing any monitoring facility) such interface was created. Next to the monitoring services we designed and implemented a simple statistical pro ler. Both the user programs and the whole operating system can be pro led. Two userspace applications were created for this purpose.
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