Case study: Improving the Performance of Automated Acceptance Testing with Selenium

Tänapäeval on väga suur osa elust koondunud veebi ning seetõttu on ettevõtted peaaegu et kohustatud oma veebilehtesid korralikult haldama. Samas on veebilehtede arendamine ja ülalpidamine keeruline ja kallis töö. Lehe nõuetekohase käitumise tagamiseks kasutavad arendajad tihtipeale brauseripõhiseid vastuvõtuteste. Brauseripõhiste vastuvõtutestide probleem seisneb aga selles, et need on aeglased. Sageli on nende kasutamine pideva integratsiooni tõttu keeruline, sest vastuvõtutestide käitusaeg on sedavõrd pikk, et arendaja peab enne tagasiside saamist juba järgmise ülesande juurde liikuma. See omakorda pikendab tarneaegu, muudab vigade avastamise ebaefektiivsemaks, raskendab lähtekoodis vigade jälitamist ja vähendab arendajate motivatsiooni.\n\rSaleMove’il on kõrged kvaliteedistandardid ja järgitakse TDD põhimõtteid. Lisaks TDD-le on SaleMove’is laiahaardelised vastuvõtutestid – üle 220 unikaalse vastuvõtutesti paralleelselt üheksas erinevas brauseris. Selenium on tööriist, mille abil saab luua automaatseid funktsionaalseid teste veebirakendustele. Juhtumiuuringu eesmärgiks oli analüüsida ja optimeerida SaleMove’i vastuvõtutestide keskkonda. Sihiks seati vähendada vastuvõtutestide käitusaega 50 minutilt umbes kümnele minutile. See aitas lühendada tarneaegu, parandada vigu kiiremini ja tõsta arendajate rahulolu.\n\rUuringu käigus analüüsiti SaleMove’i vastuvõtutestide kitsaskohti. Esiteks analüüsiti testjuhtude komplekti ning testi alustamise ja lõpetamise aegu. Seejärel tuvastati kitsaskohad, optimeeriti vastuvõtutestide keskkonda ning tehti vajalikud parandused. Analüüsiti Seleniumi hajusalt jooksutamist ehk jooksutati iga testi hajusas keskkonnas paralleelselt teiste testidega. Antud töös kirjeldati detailselt, kuidas arendati hajusat keskkonda ja koguti tulemused loetavasse formaati. Viimaseks dokumenteeriti vastuvõtutestide hajusa keskkonna plussid ja miinused ning arutati, kuidas seda tulevikus veelgi paremaks muuta.\n\rKokkuvõttes vähendati SaleMove’i vastuvõtutestide keskkonna käitusaega 50 minutilt 13 minutile ning seda suuresti tänu hajutamisele. See omakorda vähendas tarneaegu, suurendas arendajate rahulolu ja oli paljuski muus mõttes kasulik. Samas muutus vastuvõtukeskkonna ülesehitus keerukamaks ning lisaks suurenesid hajusa keskkonna tõttu nõuded riistvarale.In the current world, where everything is on the web, it is nearly a requirement for a company to manage its website. Building a complex website has its costs though – it is difficult and expensive to maintain and develop. Developers often use browser based acceptance tests to assure that the page behaves as dictated by the requirements. The problem with browser based acceptance tests is that they are slow. It is often difficult to use them in continuous integration since the running time of the test suite is so long that the developer moves on to the next task. This increases deployment cycle times, reduces bug-catching rate, makes it hard to trace a bug back to the source commit, and frustrates developers in general. \n\rSaleMove Inc has high standards of quality and follows the TDD principles. In addition to doing TDD, SaleMove has an extensive Selenium-based acceptance test environment, running over 220 tests in 9 different browsers in parallel. Selenium is an automated tool for creating functional tests for web applications [1]. We conducted a case study to analyse and improve SaleMove’s acceptance test environment. The goal of the study was to reduce the total acceptance test time of about 50 minutes to around 10 minutes. This allowed us to shorten release cycles, make bug fixing faster and developers happier.\n\rDuring the study, we analysed the bottlenecks of the SaleMove’s acceptance test environment. First, we analysed the test suite and test case startup and the teardown times. Then we identified the bottlenecks of the acceptance test environment and made improvements. We analysed the effect of running Selenium in full cluster mode, i.e., each test running in a clustered hub in parallel with other tests. In this thesis, we describe in detail how we implemented the clustered mode, and how we aggregated test results into a readable format. Finally, we document the gains and costs of this clustered setup and suggest future improvements.\n\rIn summary, we managed to shorten SaleMove’s acceptance test time to around 13 minutes in full cluster mode. This reduces deployment cycle times, increases developer satisfaction and has other benefits. This comes at the cost of higher complexity of the acceptance test environment and of additional machines that are needed for the clustered mode

Parallel Wilcoxon signed-rank tests

Statistilisi teste kasutatakse tuvastamaks kuidas erinevad eksperimentaalsed stiimulid mõjutavad uuritavaid suurusi. Antud töös uuritav Wilcoxoni test on üks vähestest statilistest testidest, mida saab kasutada juhul kui grupi sees olev loomulik varieeruvus pole normaaljaotusega. Selliste testide kasutamine on tavapärane bioloogiliste andmete uurimisel. Sellest tulenevalt kasutatakse seda testi bioinformaatika, algoritmika ja andmekaeve grupi poolt geenide uurimiseks, analüüsimiseks ja andmekaeveks, bioloogiliseks andmekaeveks ja muudeks ülesanneteks. Praegused implementatsioonid Wilcoxoni astaku testist on optimeerimata ja aeglased. See projekt vaatab Wilcoxoni testi põhiomadusi ning uurib kuidas selle implementatsioone optimeerida. Selleks, et implementatsiooni teha täpsemaks, uuritakse Wilcoxoni statistiku ja Gaussi jaotuse seost. Selleks, et implementatsioone kiiremaks teha, kasutatakse dünaamilise programmeerimise meetodeid, et säästa arvutusaega. Optimeerimisega tehti teste nii kiiremaks kui ka täpsemaks. Antud töös loodi täpne ja kiire Wilcoxoni testi implementatsioon C++ jagatud teek. Selle projekti skoobis on ka nimetatud teegi integreerimine käsureaga ja GNU-R projektiga. Tänu enda jagatud teegi olemusele, on seda lihtne kasutada ja implementeerida ka teistes tööriistades.Statistical tests are used to find out if some sort of experimental stimulation affects observable features. In this paper we researched Wilcoxon signed-rank test which is one of the few statistical tests that can be used when the natural variation inside the group is not normally distributed. The test is used by Bioinformatics, Algorithmics and Data mining group research for gene regulation, gene expression data analysis, biological data mining and others. BIIT is a joint research group between the Department of Computer Science (University of Tartu), Quretec, and the Estonian Biocenter. The current implementations of the Wilcoxon signed-rank tests are slow and unoptimized. This project looked into the foundations of Wilcoxon signed-rank test, its current implementations and how to optimize it. In order to make the implementation more accurate, the relationship between Wilcoxon statistic and Gaussian approximate was observed. In order to make the implementation faster, some dynamic programming methods were used to save computation time. The purpose of optimizing was to make it more accurate and speed up the test running. In this project an accurate and fast Wilcoxon test shared library was created. In the scope of this project, the library was integrated with two tools - command line and GNU-R. Due to the nature of shared library, it will be easy integrate the library with any other tools one might desire

The Influence of Exogenous Fat and Water on Lumbar Spine Bone Mineral Density in Healthy Volunteers

∙ The authors have no financial conflicts of interest. © Copyright: Yonsei University College of Medicine 2012 This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial Licens

Quantitative analysis of late gadolinium enhancement in hypertrophic cardiomyopathy: comparison of diagnostic performance in myocardial fibrosis between gadobutrol and gadopentetate dimeglumine

The purpose of this study was to compare different semi-automated late gadolinium enhancement (LGE) quantification techniques using gadobutrol and gadopentetate dimeglumine contrast agents with regard to the diagnosis of fibrotic myocardium in patients with hypertrophic cardiomyopathy (HCM). Thirty patients with HCM underwent two cardiac MRI protocols with use of gadobutrol and gadopentetate dimeglumine. Contrast-tonoise ratio (CNR) between LGE area and remote myocardium (CNRremote), between LGE area and left ventricular blood pool (CNRpool), and signal-to-noise ratio (SNR) in LGE were compared. The presence and quantity of LGE were determined by visual assessment. With signal threshold versus reference mean (STRM) based thresholds of 2 SD, 5 SD, and 6 SD above the mean signal intensity (SI) of reference myocardium, the full-width at half-maximum (FWHM) technique was used. The volume and segments of the LGE area were compared between the two types of contrast agents. LGE was present in 26 of 30 (86.6%) patients in both protocols. The CNRremote of fibrotic myocardium in gadobutrol and gadopentetate dimeglumine agents was 26.82 ± 14.24 and 21.46 ± 10.59, respectively (P < 0.05). The CNRpool was significantly higher in gadobutrol (9.32 ± 7.64 vs. 6.39 ± 6.11, P < 0.05). The SNR was higher in gadobutrol (33.36 ± 14.35 vs. 27.53 ± 10.91, P < 0.05). The volume of scar size in MR images acquired with gadobutrol were significantly higher than those with gadopentetate dimeglumine (P < 0.05), and the STRM of 5 SD technique showed the greatest agreement with visual assessment (ICC = 0.99) in both examinations. There was no significant difference in fibrotic segments of the fibrotic myocardium in the LGE area (P < 0.05). This study proved that the Gadobutrol was an effective contrast agent for LGE imaging with superior delineation of fibrotic myocardium as compared to gadopentetate dimeglumine. The 5 SD technique yields the closest approximation of the extent of LGE identified by visual assessment