A General-Purpose Provenance Library

Most provenance capture takes place inside particular tools - a workflow engine, a database, an operating system, or an application. However, most users have an existing toolset - a collection of different tools that work well for their needs and with which they are comfortable. Currently, such users have limited ability to collect provenance without disrupting their work and changing environments, which most users are hesitant to do. Even users who are willing to adopt new tools, may realize limited benefit from provenance in those tools if they do not integrate with their entire environment, which may include multiple languages and frameworks. We present the Core Provenance Library (CPL), a portable, multi-lingual library that application programmers can easily incorporate into a variety of tools to collect and integrate provenance. Although the manual instrumentation adds extra work for application programmers, we show that in most cases, the work is minimal, and the resulting system solves several problems that plague more constrained provenance collection systems.Engineering and Applied Science

Provenance Map Orbiter: Interactive Exploration of Large Provenance Graphs

Provenance systems can produce enormous provenance graphs that can be used for a variety of tasks from determining the inputs to a particular process to debugging entire workflow executions or tracking difficult-to-find dependencies. Visualization can be a useful tool to sup- port such tasks, but graphs of such scale (thousands to millions of nodes) are notoriously difficult to visualize. This paper presents the Provenance Map Orbiter, a tool for interactively exploring large provenance graphs using graph summarization and semantic zoom. It presents its users with a high-level abstracted view of the graph and the ability to incrementally drill down to the details.Engineering and Applied Science

Implementation and Extension of the Technical Documentation Testing Framework

Práca sa zaoberá automatizáciou testovania technickej dokumentácie napísanej v značkovacom jazyku AsciiDoc pomocou open-source frameworku testovania technickej dokumentácie Emender implementovaného na CI/CD platforme. Framework bol rozšírený o webovú aplikáciu emenderwebservice s REST API, ktorá poskytuje užívateľské grafické rozhranie s výsledkami testov a mechanizmom na odrieknutie falošne pozitívnych výsledkov testov. Webová aplikácia bola vytvorená pomocou WSGI frameworku na tvorbu webových aplikácií Flask s databázou ktorá umožňuje agregáciu výsledkov testov a ich unikátnu identifikáciu. Aplikácia uľahčuje prístup ku výsledkom testov vygenerovaných frameworkom Emender v CI/CD systémoch a poskytuje technical writer-om ucelené užívateľské prostredie.The thesis discusses automated testing of technical documentation written in AsciiDoc markup language using open-source documentation testing framework Emender implemented in CI/CD. The framework was extended with a RESTful web application emenderwebservice, providing a graphical user interface with test results and a mechanism to waive false positive test results. Web application was implemented with Flask WSGI web application framework along with a database enabling aggregation and unique test identification. The application simplifies access to test results generated by Emender in CI/CD and provides a concise graphical user interface for technical writers.

Mixed-use Building in Brno, Sadova - Execution of Superstructure

Obsahom tejto bakalárskej práce je riešenie technologickej etapy hrubej vrchnej stavby polyfunkčnej budovy v Brne. Práca zahŕňa sprievodnú a súhrnnú technickú správu, technologické predpisy pre montáž prefabrikovaného skeletu a pre murované konštrukcie. Technologické predpisy sú doplnené návrhom zariadenia staveniska vrátane technickej správy, kontrolným a skúšobným plánom pre montáž prefabrikovaného skeletu, časovým plánom, návrhom strojnej zostavy a posúdením výberu zdvíhacieho mechanizmu.The subject of this bachelor thesis is the deal with technological stage of the rough superstructure of a mixed-use building in Brno. The thesis contains accompanying and summary technical reports, technological regulations for the assembly of the prefabricated skeleton and for masonry constructions. Technological regulations are attached to design of site equpiment including engineering report, checking and testing plans for the assembly of the prefabricated skeleton, time schedule, proposal of machine assemblies and assessment of lifting mechanism selection.

Tracking Back References in a Write-Anywhere File System

Many file systems reorganize data on disk, for example to defragment storage, shrink volumes, or migrate data between different classes of storage. Advanced file system features such as snapshots, writable clones, and deduplication make these tasks complicated, as moving a single block may require finding and updating dozens, or even hundreds, of pointers to it. We present Backlog, an efficient implementation of explicit back references, to address this problem. Back references are file system meta-data that map physical block numbers to the data objects that use them. We show that by using LSM-Trees and exploiting the write-anywhere behavior of modern file systems such as NetApp R WAFL R or btrfs, we can maintain back reference meta-data with minimal overhead (one extra disk I/O per 102 block operations) and provide excellent query performance for the common case of queries covering ranges of physically adjacent blocks.Engineering and Applied Science

Performance Introspection of Graph Databases

The explosion of graph data in social and biological networks, recommendation systems, provenance databases, etc. makes graph storage and processing of paramount importance. We present a performance introspection framework for graph databases, PIG, which provides both a toolset and methodology for understanding graph database performance. PIG consists of a hierarchical collection of benchmarks that compose to produce performance models; the models provide a way to illuminate the strengths and weaknesses of a particular implementation. The suite has three layers of benchmarks: primitive operations, composite access patterns, and graph algorithms. While the framework could be used to compare different graph database systems, its primary goal is to help explain the observed performance of a particular system. Such introspection allows one to evaluate the degree to which systems exploit their knowledge of graph access patterns. We present both the PIG methodology and infrastructure and then demonstrate its efficacy by analyzing the popular Neo4j and DEX graph databases.Engineering and Applied Science

Collecting Provenance via the Xen Hypervisor

The Provenance Aware Storage Systems project (PASS) currently collects system-level provenance by intercepting system calls in the Linux kernel and storing the provenance in a stackable filesystem. While this approach is reasonably efficient, it suffers from two significant drawbacks: each new revision of the kernel requires reintegration of PASS changes, the stability of which must be continually tested; also, the use of a stackable filesystem makes it difficult to collect provenance on root volumes, especially during early boot. In this paper we describe an approach to collecting system-level provenance from virtual guest machines running under the Xen hypervisor. We make the case that our approach alleviates the aforementioned difficulties and promotes adoption of provenance collection within cloud computing platforms.Engineering and Applied Science

Assessing the Impact of a Supervised Classification Filter on Flow-based Hybrid Network Anomaly Detection

Constant evolution and the emergence of new cyberattacks require the development of advanced techniques for defense. This paper aims to measure the impact of a supervised filter (classifier) in network anomaly detection. We perform our experiments by employing a hybrid anomaly detection approach in network flow data. For this purpose, we extended a state-of-the-art autoencoder-based anomaly detection method by prepending a binary classifier acting as a prefilter for the anomaly detector. The method was evaluated on the publicly available real-world dataset UGR'16. Our empirical results indicate that the hybrid approach does offer a higher detection rate of known attacks than a standalone anomaly detector while still retaining the ability to detect zero-day attacks. Employing a supervised binary prefilter has increased the AUC metric by over 11%, detecting 30% more attacks while keeping the number of false positives approximately the same

Making a Cloud Provenance-Aware

The advent of cloud computing provides a cheap and convenient mechanism for scientists to share data. The utility of such data is obviously enhanced when the provenance of the data is also available. The cloud, while convenient for storing data, is not designed for storing and querying provenance. In this paper, we present desirable properties for distributed provenance storage systems and present design alternatives for storing data and provenance on Amazon’s popular Web Services platform (AWS). We evaluate the properties satisfied by each approach and analyze the cost of storing and querying provenance in each approach.Engineering and Applied Science

Provenance Integration Requires Reconciliation

While there has been a great deal of research on provenance systems, there has been little discussion about challenges that arise when making different provenance systems interoperate. In fact, most of the literature focuses on provenance systems in isolation and does not discuss interoperability – what it means, its requirements, and how to achieve it. We designed the Provenance-Aware Storage System to be a general- purpose substrate on top of which it would be “easy” to add other provenance-aware systems in a way that would provide “seamless integration” for the provenance captured at each level. While the system did exactly what we wanted on toy problems, when we began integrating StarFlow, a Python-based workflow/provenance system, we discovered that integration is far trickier and more subtle than anyone has suggested in the literature. This work describes our experience undertaking the integration of StarFlow and PASS, identifying several important additions to existing provenance models necessary for interoperability among provenance systems.Engineering and Applied Science