The Experts below are selected from a list of 1092 Experts worldwide ranked by ideXlab platform
Zhou Gongye - One of the best experts on this subject based on the ideXlab platform.
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new kind of metadata management strategy based on object storage
Computer Engineering, 2012Co-Authors: Zhou GongyeAbstract:On the basis of the research of previous object storage metadata management strategies,this paper puts forward a new kind of metadata management strategy.The method is to divide namespace Directory into neutron trees,and compute with hash function using the combination of the Root Directory name and file name.Metadata Server(MDS) determines its storage path according to the hash value.Experimental result shows that this new kind of metadata management tactics can avoid the massive metadata migration problems and network overhead problems in dealing with metadata rename operation and modify filename.
Mondal, Mendeley S Data) - One of the best experts on this subject based on the ideXlab platform.
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Data files for Mahtab: Phase-wise Acceleration of Regression Testing for C
2019Co-Authors: Mondal, Mendeley S Data)Abstract:Raw log files (plain-text) and processed spreadsheets (.ods) corresponding to experimental data in Mahtab: Phase-wise Acceleration of Regression Testing for C. Plain-text files contained raw data from program's execution. Spreadsheets contain summarized data from text-files, corresponding to plots presented throughout the paper. The plots have also been included in associated .ods files. The Root Directory contains the following tarballs: -- mahtab_data.tar.gz (data used in experiments). -- mahtab_tool.tar.gz (source codes for our software tool)
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Data files for Mahtab: Phase-wise Acceleration of Regression Testing for C
2019Co-Authors: Mondal, Mendeley S Data)Abstract:Software regression testing consists of offline, online, and execution phases which are executed sequentially. The offline phase involves code instrumentation and test-coverage collection. Subsequently, the online phase performs program differencing, test-suite selection and prioritization. Finally, the selected test-cases are executed against the new version of software for its re-validation. Regression testing is a time-consuming process and is often on the critical path of the project. To improve the turn-around time of software development cycle, our goal is to reduce regression testing time across all phases using multi-core parallelization. This poses several challenges that stem from I/O, dependence on third-party libraries, and inherently sequential components in the overall testing process. We propose parallelization test-windows to effectively partition test-cases across threads. To measure the benefit of prioritization coupled with multi-threaded execution, we propose a new metric, EPSilon, for rewarding failure observation frequency in the timeline of test-execution. To measure the rate of code-change coverage due to regression test prioritization, we introduce ECC, a variant of the widely used APFD metric. We illustrate the effectiveness of our approach using the popular Software-artifact Infrastructure Repository (SIR) and five real-world projects from GitHub. We show that for SIR programs, parallel regression testing achieves an end-to-end geometric mean speedup of 4.72× compared to sequential RTS (and 2.44× against RetestAll). We achieve a geometric mean boost (EBF) of 1.6× in effectiveness (EPSilon) of test prioritization, using up to 16 threads. For GitHub projects used in our study, we observed end-to-end speedup of 3.90× compared to sequential RTS, and EBF of 1.43×, using up to 32 threads. All the experiments were performed on a system with a 20-core (40 threads with hyper-threading) Intel Xeon CPU E5-2640 v4 clocked at 2.40GHz having 64GB RAM running CentOS Linux release 7.5.1804 (Core) operating system. While Mahtab framework was compiled using g++ 5.3.1, the benchmark programs were compiled using clang frontend of LLVM. In this dataset, we have included raw log files (in plain-text) and processed spreadsheets (.ods) corresponding to experimental data in Mahtab: Phase-wise Acceleration of Regression Testing for C. Plain-text files contain raw data from program's execution. Spreadsheets contain summarized data from text-files, corresponding to plots and tabulations presented throughout the paper. All plots have also been included in associated .ods files. The Root Directory contains the following tarballs: -- mahtab_data.tar.gz (data used in experiments). -- mahtab_tool.tar.gz (source codes for our software tool)
Ruiz Juan-carlos - One of the best experts on this subject based on the ideXlab platform.
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Robustness assessment through iterative statistical fault injection: LEON3 processor as a case study
2018Co-Authors: Tuzov Ilya, De Andrés David, Ruiz Juan-carlosAbstract:Dataset exemplifies an approach of iterative statistical fault injection to assess the robustness of HDL models. Contents: 1. Results of exhaustive fault injection experiments (bit-flip faults) into LEON3 processor model; 2. Interactive querying interface, allowing to obtain custom samples from exhaustive results, and visualize them; 3. Python scripts simulating 3 approaches to statistical fault injection: conservative, error-driven, time-driven. Installation guide: 1. Ensure to have python ver. 2.x installed. Type in terminal (cmd console in Windows): “python --version” – if the output looks like > Python 2.x.x – python is installed. Otherwise download and install 2.x.x distribution: https://www.python.org/ Add python installation path to environment path variable. 2. Ensure to have Web-Server installed (Apache preferable). For instance, XAMPP: https://www.apachefriends.org/index.html 3. Ensure that Web-server is configured to execute CGI scripts, particularly python-scripts: In the 'httpd.conf' file (XAMMP control panel – button config in front of apache module): – search for line Options Indexes FollowSymLinks and add ExecCGI, so the resulting line looks like this: Options Indexes FollowSymLinks ExecCGI – search for #AddHandler cgi-script .cgi, uncomment (remove #), and append “.py” to this line, so the results looks like: AddHandler cgi-script .cgi .pl .asp .py 4. Unpack the contents of *.zip package into the folder on the Web Server. For instance into 'Web-server Root folder'/Dataset. The Web-Server Root can be configured in the ‘httpd.conf’ file in the DocumentRoot section, for instance: DocumentRoot "F:/HTWEB" ... 5. In the web-browser navigate to the Root Directory of extracted package: http://localhost/Dataset/index.html
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Example results for use-cases of DAVOS toolkit (dependability assessment, verification, optimisation and selection of hardware models)
2018Co-Authors: Tuzov Ilya, De Andrés David, Ruiz Juan-carlosAbstract:This dataset exemplifies the results that can be obtained for several basic experimentation scenarios by means of DAVOS toolkit, available under MIT licence at https://github.com/IlyaTuzov/DAVOS Particular experimentation scenarios are: - Dependability assessment (LEON3 processor core) - Dependability benchmarking of implementation alternatives (MC8051 processor core) - Dependability-aware design space exploration (when implementing PIC core by Xilinx ISE toolkit) Installation steps. 1. Ensure to have python ver. 2.x installed. Type in terminal (cmd console in Windows): “python --version” – if the output looks like > Python 2.x.x – python is installed. Otherwise download and install 2.x.x distribution: https://www.python.org/ Add python installation path to environment path variable. 2. Ensure to have Web-Server installed (Apache preferable). For instance, XAMPP: https://www.apachefriends.org/index.html 3. Ensure that Web-server is configured to execute CGI scripts, particularly python-scripts: In the 'httpd.conf' file (XAMMP control panel – button config in front of apache module): – search for line Options Indexes FollowSymLinks and add ExecCGI, so the resulting line looks like this: Options Indexes FollowSymLinks ExecCGI – search for #AddHandler cgi-script .cgi, uncomment (remove #), and append “.py” to this line, so the results looks like: AddHandler cgi-script .cgi .pl .asp .py 4. Unpack the contents of *.zip package into the folder on the Web Server. For instance into 'Web-server Root folder'/Dataset. The Web-Server Root can be configured in the ‘httpd.conf’ file in the DocumentRoot section, for instance: DocumentRoot "F:/HTWEB" ... 5. In the web-browser navigate to the Root Directory of extracted package: http://localhost/Dataset/index.html
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Robustness assessment via simulation-based fault injection of the implementation level models of the LEON3, MC8051, and PIC microcontrollers in presence of stuck-at, bit-flip, pulse, and delay fault models
2018Co-Authors: Tuzov Ilya, De Andrés David, Ruiz Juan-carlosAbstract:This dataset package contains the results of fault injection experiments for RTL and implementation-level models 3 microprocessors (LEON3, MC8051, PIC). 1. Package contents: - raw traces of fault injection experiments: *.lst files - analysis results grouped by fault models: *.html files in the /REPORT subfolders - summary for each targeted HDL model and fault model: index.html in each design folder To facilitate the navigation through the contents, it is organized as a tree of *.html pages. The Root page is 'index.html' in the archive Root. Additionally, to observe the raw traces for each experiment in the convenient form, the *.lst files are processed on the fly by custom python-script, returning the interactive *.html page. Each observation trace is a table, where: - each row represents an observation vector, comprising {simulation time stamp}, {flags}, {internal state}, {outputs}. - each cell is highlighted: a) green if matches with reference trace (fault-free simulation), b) red if mismatches with reference trace, denoting error for internals / failure for outputs, c) violet in case of vector whose timestamp was not in reference (unexpected transition). These highlighting options can be customized by modifying the linked *.css files. 2. Installation 2.1 Ensure to have Web-Server installed (Apache preferable). For instance, XAMPP: https://www.apachefriends.org/index.html 2.2 Ensure to have python ver. 2.x installed. Type in terminal (cmd console in Windows): “python --version” – if the output looks like > Python 2.x.x – python is installed. Otherwise install the relevant 2.x.x distribution: https://www.python.org/ Add python installation path to environment path variable. 2.2 Ensure that Web-server is configured to execute CGI scripts, particularly python-scripts: In the 'httpd.conf' file (XAMMP control panel – button config in front of apache module): – search for line Options Indexes FollowSymLinks and add ExecCGI, so the resulting line looks like this: Options Indexes FollowSymLinks ExecCGI – search for #AddHandler cgi-script .cgi, uncomment (remove #), and append “.py” to this line, so the resulting line: AddHandler cgi-script .cgi .pl .asp .py 2.3 Unpack the *.zip package into the folder on the Web Server. For instance 'Web-server Root folder'/ExperimentalResults. The Web-Server Root can be configured in the ‘httpd.conf’ file in the DocumentRoot section, for instance: DocumentRoot "F:/HTWEB" ... 2.4 In the web-browser navigate to the Root Directory of extracted package: http://localhost/ExperimentalResults/index.html 3. How to read the contents The Root page contains links to different analysis reports, for each HDL design under study and considered fault models. The pages on the first tree level, represent the summary for each injection campaign, describing the rate of failure modes, number of experiments, latencies, and supplementary info. The pages on the second tree level are the detailed analysis reports for each experiment, detailing the fault target, parameters of injected fault, detected failure mode, number of errors, etc. The cells of the first column are highlighted a) in green if injection did not cause the failure, b) in red otherwise. The links in this first column navigate to the detailed traces for each experiment. The latter requires that Web-server is configured to execute the python-scripts (see section 2 - Installation); otherwise the raw traces (*.lst files in ./results folders) can be observed by any text editor (notepad++, etc.).
C Tarimo - One of the best experts on this subject based on the ideXlab platform.
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a review of adopter s common misconfigurations of virtual machines the case of tanzania
Huria: Journal of the Open University of Tanzania, 2018Co-Authors: Said Ally, Noorali T Jiwaji, C TarimoAbstract:Adoption and use of hypervisors and virtual machines have become heart of virtual server computing and are currently a primary choice to store and share data across different public and private sectors. However, one of the major security threats is on meager adopter’s knowledge on proper handling of hypervisor installation, VMs creation and configurations. This paper exposes distinct security vulnerabilities of virtualized systems that are caused by the adopters due to various system misconfigurations such as use of unified installer across virtual infrastructure, level of security enhancement in type 2 hypervisors, presence of untouched default settings in open source hypervisors, usage of vendor lock in VMs file formats, ad hoc creation of VMs and allocation of computing resources especially virtual CPU, RAM and HDD. Furthermore, undecided size of key Linux directories including /home Directory, /boot Directory, /var Directory, Root (/) Directory, /temp Directory and swap have also been assessed. To undertake this study, server configurations in 15 public and 9 private organizations were screened. A total of 31 purposively selected server administrators were interviewed guided by a checklist of questions in a semi-structured questionnaire. A quick observation obtained from the findings of this study suggests that server virtualization adopters operate at high security risks due to existence of uncoordinated and unsecured VMs configuration due to lack of required expertise. Lack of regular system auditing and monitoring turn the adopters into vulnerable and target of attack at any time without the adopter’s knowledge. The need for adopters to observe best practices towards adoption and use of virtualization software is vital.
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A Review of Adopter’s Common Misconfigurations of Virtual Machines: The Case of Tanzania
Huria: Journal of the Open University of Tanzania, 2018Co-Authors: Said Ally, Noorali T Jiwaji, C TarimoAbstract:Adoption and use of hypervisors and virtual machines have become heart of virtual server computing and are currently a primary choice to store and share data across different public and private sectors. However, one of the major security threats is on meager adopter’s knowledge on proper handling of hypervisor installation, VMs creation and configurations. This paper exposes distinct security vulnerabilities of virtualized systems that are caused by the adopters due to various system misconfigurations such as use of unified installer across virtual infrastructure, level of security enhancement in type 2 hypervisors, presence of untouched default settings in open source hypervisors, usage of vendor lock in VMs file formats, ad hoc creation of VMs and allocation of computing resources especially virtual CPU, RAM and HDD. Furthermore, undecided size of key Linux directories including /home Directory, /boot Directory, /var Directory, Root (/) Directory, /temp Directory and swap have also been assessed. To undertake this study, server configurations in 15 public and 9 private organizations were screened. A total of 31 purposively selected server administrators were interviewed guided by a checklist of questions in a semi-structured questionnaire. A quick observation obtained from the findings of this study suggests that server virtualization adopters operate at high security risks due to existence of uncoordinated and unsecured VMs configuration due to lack of required expertise. Lack of regular system auditing and monitoring turn the adopters into vulnerable and target of attack at any time without the adopter’s knowledge. The need for adopters to observe best practices towards adoption and use of virtualization software is vital.
Tuzov Ilya - One of the best experts on this subject based on the ideXlab platform.
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Robustness assessment through iterative statistical fault injection: LEON3 processor as a case study
2018Co-Authors: Tuzov Ilya, De Andrés David, Ruiz Juan-carlosAbstract:Dataset exemplifies an approach of iterative statistical fault injection to assess the robustness of HDL models. Contents: 1. Results of exhaustive fault injection experiments (bit-flip faults) into LEON3 processor model; 2. Interactive querying interface, allowing to obtain custom samples from exhaustive results, and visualize them; 3. Python scripts simulating 3 approaches to statistical fault injection: conservative, error-driven, time-driven. Installation guide: 1. Ensure to have python ver. 2.x installed. Type in terminal (cmd console in Windows): “python --version” – if the output looks like > Python 2.x.x – python is installed. Otherwise download and install 2.x.x distribution: https://www.python.org/ Add python installation path to environment path variable. 2. Ensure to have Web-Server installed (Apache preferable). For instance, XAMPP: https://www.apachefriends.org/index.html 3. Ensure that Web-server is configured to execute CGI scripts, particularly python-scripts: In the 'httpd.conf' file (XAMMP control panel – button config in front of apache module): – search for line Options Indexes FollowSymLinks and add ExecCGI, so the resulting line looks like this: Options Indexes FollowSymLinks ExecCGI – search for #AddHandler cgi-script .cgi, uncomment (remove #), and append “.py” to this line, so the results looks like: AddHandler cgi-script .cgi .pl .asp .py 4. Unpack the contents of *.zip package into the folder on the Web Server. For instance into 'Web-server Root folder'/Dataset. The Web-Server Root can be configured in the ‘httpd.conf’ file in the DocumentRoot section, for instance: DocumentRoot "F:/HTWEB" ... 5. In the web-browser navigate to the Root Directory of extracted package: http://localhost/Dataset/index.html
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Example results for use-cases of DAVOS toolkit (dependability assessment, verification, optimisation and selection of hardware models)
2018Co-Authors: Tuzov Ilya, De Andrés David, Ruiz Juan-carlosAbstract:This dataset exemplifies the results that can be obtained for several basic experimentation scenarios by means of DAVOS toolkit, available under MIT licence at https://github.com/IlyaTuzov/DAVOS Particular experimentation scenarios are: - Dependability assessment (LEON3 processor core) - Dependability benchmarking of implementation alternatives (MC8051 processor core) - Dependability-aware design space exploration (when implementing PIC core by Xilinx ISE toolkit) Installation steps. 1. Ensure to have python ver. 2.x installed. Type in terminal (cmd console in Windows): “python --version” – if the output looks like > Python 2.x.x – python is installed. Otherwise download and install 2.x.x distribution: https://www.python.org/ Add python installation path to environment path variable. 2. Ensure to have Web-Server installed (Apache preferable). For instance, XAMPP: https://www.apachefriends.org/index.html 3. Ensure that Web-server is configured to execute CGI scripts, particularly python-scripts: In the 'httpd.conf' file (XAMMP control panel – button config in front of apache module): – search for line Options Indexes FollowSymLinks and add ExecCGI, so the resulting line looks like this: Options Indexes FollowSymLinks ExecCGI – search for #AddHandler cgi-script .cgi, uncomment (remove #), and append “.py” to this line, so the results looks like: AddHandler cgi-script .cgi .pl .asp .py 4. Unpack the contents of *.zip package into the folder on the Web Server. For instance into 'Web-server Root folder'/Dataset. The Web-Server Root can be configured in the ‘httpd.conf’ file in the DocumentRoot section, for instance: DocumentRoot "F:/HTWEB" ... 5. In the web-browser navigate to the Root Directory of extracted package: http://localhost/Dataset/index.html
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Robustness assessment via simulation-based fault injection of the implementation level models of the LEON3, MC8051, and PIC microcontrollers in presence of stuck-at, bit-flip, pulse, and delay fault models
2018Co-Authors: Tuzov Ilya, De Andrés David, Ruiz Juan-carlosAbstract:This dataset package contains the results of fault injection experiments for RTL and implementation-level models 3 microprocessors (LEON3, MC8051, PIC). 1. Package contents: - raw traces of fault injection experiments: *.lst files - analysis results grouped by fault models: *.html files in the /REPORT subfolders - summary for each targeted HDL model and fault model: index.html in each design folder To facilitate the navigation through the contents, it is organized as a tree of *.html pages. The Root page is 'index.html' in the archive Root. Additionally, to observe the raw traces for each experiment in the convenient form, the *.lst files are processed on the fly by custom python-script, returning the interactive *.html page. Each observation trace is a table, where: - each row represents an observation vector, comprising {simulation time stamp}, {flags}, {internal state}, {outputs}. - each cell is highlighted: a) green if matches with reference trace (fault-free simulation), b) red if mismatches with reference trace, denoting error for internals / failure for outputs, c) violet in case of vector whose timestamp was not in reference (unexpected transition). These highlighting options can be customized by modifying the linked *.css files. 2. Installation 2.1 Ensure to have Web-Server installed (Apache preferable). For instance, XAMPP: https://www.apachefriends.org/index.html 2.2 Ensure to have python ver. 2.x installed. Type in terminal (cmd console in Windows): “python --version” – if the output looks like > Python 2.x.x – python is installed. Otherwise install the relevant 2.x.x distribution: https://www.python.org/ Add python installation path to environment path variable. 2.2 Ensure that Web-server is configured to execute CGI scripts, particularly python-scripts: In the 'httpd.conf' file (XAMMP control panel – button config in front of apache module): – search for line Options Indexes FollowSymLinks and add ExecCGI, so the resulting line looks like this: Options Indexes FollowSymLinks ExecCGI – search for #AddHandler cgi-script .cgi, uncomment (remove #), and append “.py” to this line, so the resulting line: AddHandler cgi-script .cgi .pl .asp .py 2.3 Unpack the *.zip package into the folder on the Web Server. For instance 'Web-server Root folder'/ExperimentalResults. The Web-Server Root can be configured in the ‘httpd.conf’ file in the DocumentRoot section, for instance: DocumentRoot "F:/HTWEB" ... 2.4 In the web-browser navigate to the Root Directory of extracted package: http://localhost/ExperimentalResults/index.html 3. How to read the contents The Root page contains links to different analysis reports, for each HDL design under study and considered fault models. The pages on the first tree level, represent the summary for each injection campaign, describing the rate of failure modes, number of experiments, latencies, and supplementary info. The pages on the second tree level are the detailed analysis reports for each experiment, detailing the fault target, parameters of injected fault, detected failure mode, number of errors, etc. The cells of the first column are highlighted a) in green if injection did not cause the failure, b) in red otherwise. The links in this first column navigate to the detailed traces for each experiment. The latter requires that Web-server is configured to execute the python-scripts (see section 2 - Installation); otherwise the raw traces (*.lst files in ./results folders) can be observed by any text editor (notepad++, etc.).
