April, 2019

How to Test Software, Part I: Mocking, Stubbing, and Contract Testing


In my last post , I talked about building a structured path to production, which tests to include, when to do them, and why. In this post, we’ll get into exactly how to do each kind of test. We’ll cover the techniques of mocking and stubbing and test-driven development to help each testing layer.

Who has the fastest website in F1?

CSS - Tricks

7 ways to tidy up your test code

TechBeacon Testing

Your test code is a mess. You're not quite sure where anything is anymore. The fragility of it is causing your builds to fail. You're hesitant to make any changes for fear of breaking something else. The bottom line is that your tests do not spark joy, as organizing guru Marie Kondo would say. App Dev & Testing, Testing, Application Testing, Special Coverage: STAREAST Conference 2019

Code 82

Why Page Speed Scores can be Dangerous


All of the popular speed testing tools typically provide a page speed score along with their objective results. Google PageSpeed Insights has a their “Speed Score.” ” Pingdom has a “Performance Grade.” ” WebPageTest has their five A-F grades.

Speed 112

Vision and Execution Leader – 2019 Gartner Magic Quadrant for APM


Dynatrace news. If you hadn’t already heard the news, the entire Dynatrace team is immensely proud to once again been positioned as a Leader in the Gartner 2019 Magic Quadrant for Application Performance Monitoring (APM). But this year is a little different, and very special, because we made history.

Python at Netflix

The Netflix TechBlog

By Pythonistas at Netflix, coordinated by Amjith Ramanujam and edited by Ellen Livengood As many of us prepare to go to PyCon, we wanted to share a sampling of how Python is used at Netflix.

From bare-metal to Kubernetes

High Scalability

This is a guest post by Hugues Alary , Lead Engineer at Betabrand , a retail clothing company and crowdfunding platform, based in San Francisco. This article was originally published here. Early infrastructure. Rackspace. Hardware infrastructure. The scalability and maintainability issue.

Retail 271

More Trending

Tips for Technical Interviews

CSS Wizardry

Yesterday, I spoke at ITKonket in Kragujevac, Serbia. During the Q&A after my talk, one great and non-technical question I got was for general advice on interviewing at tech companies. I decided to write down (and expand on) my answer in the hope that it might help someone else, too. Disclaimer. I don’t claim to be an authority on interviewing. I don’t think this article is definitive or gospel.

Code 170

How to Tune Garbage Collection in Java


Garbage collection is the mechanism by which the JVM reclaims memory on behalf of the application when it's no longer needed. At a high level, it consists of finding objects that are no longer in use, freeing the memory associated with those objects, and occasionally compacting the heap to prevent memory fragmentation. The garbage collector performs it's work using one or more threads.

Tuning 218

Optimizing Microsoft Workload on AWS with Dynatrace Davis


Dynatrace news. Many organizations are moving their Microsoft workloads to the public cloud or have already done so.

AWS 195

Introducing SVT-AV1: a scalable open-source AV1 framework

The Netflix TechBlog

by Andrey Norkin, Joel Sole, Kyle Swanson, Mariana Afonso, Anush Moorthy, Anne Aaron Netflix Headquarters, Winchester Circle. Netflix headquarters circa 2014. It’s a nice building with good architecture!

MySQL High Availability Framework Explained – Part III: Failover Scenarios

High Scalability

In this three-part blog series, we introduced a High Availability (HA) Framework for MySQL hosting in Part I, and discussed the details of MySQL semisynchronous replication in Part II.

O(n^2) in CreateProcess

Randon ASCII

So many possible introductions to this one: Windows 7: Sheesh, I sure am slow at creating processes. Windows 10: Hold my beer…. Or how about: A) How long does CreateProcess take on Windows? B) How long would you like it to take? A) You mean you can make it as fast as I want?

Keeping master green at scale

The Morning Paper

Keeping master green at scale Ananthanarayanan et al., EuroSys’19. This paper provides a fascinating look at a key part of Uber’s software delivery machine.

Multi-Threaded Geo Web Crawler In Java


This article provides the implementation of a web crawling system called Mowglee that uses geography as the main classifying criteria for crawling.

Java 205

Deployment challenges with large enterprise systems


Dynatrace news. Dynatrace provides automated end to end monitoring of applications under a single platform. Even if this is true, in practise there is only so much the one Agent can Autodiscover and fine tuning might be required. For instance, not all deployments follow best practise.

Tackling the Pipeline Problem in the Architecture Research Community

ACM Sigarch

Computer architecture is an important and exciting field of computer science, which enables many other fields (eg. big-data processing, machine learning, quantum computing, and so on). For those of us who pursued computer architecture as a career, this is well understood.

2019 PostgreSQL Trends Report: Private vs. Public Cloud, Migrations, Database Combinations & Top Reasons Used

High Scalability

PostgreSQL is an open source object-relational database system that has soared in popularity over the past 30 years from its active, loyal, and growing community. For the 2nd year in a row, PostgreSQL has kept the title of #1 fastest growing database in the world according to the DBMS of the Year report by the experts at DB-Engines. So what makes PostgreSQL so special, and how is it being used today?

Native image lazy-loading for the web!

Addy Osmani

In this post, we'll look at the new loading attribute which brings native and lazy-loading to the web! For the curious, here's a sneak preview of it in action


How bad can it git? Characterizing secret leakage in public GitHub repositories

The Morning Paper

How bad can it git? Characterizing secret leakage in public GitHub repositories Meli et al., NDSS’19. On the one hand you might say there’s no new news here. We know that developers shouldn’t commit secrets, and we know that secrets leaked to GitHub can be discovered and exploited very quickly.

How to Monitor 1,000 Network Devices Using Sensu Go and Ansible (in Under 10 Minutes)


Network monitoring, at scale, is an age-old problem in IT. In this post, I’ll discuss a brief history of network monitoring tools — including the pain points of legacy technology when it came to monitoring thousands of devices — and share my modern-day solution using Sensu Go and Ansible. Then: Nagios and Multiple Network Monitoring Tools. I’ve spent the last ten years as a consultant for open-source monitoring architectures.

More Effective AI to Human Interactions with Dynatrace DAVIS at NYCM


Dynatrace news. Effective communication between people has and will always be a challenge. There is always a chance for misunderstandings or talking in circles until you get to the answers you expect.

Jira Cloud, Jira Server, and Jira Data Center Integrations


On a daily basis, we help our customers with connecting various SDLC tools, so that they can use best of breed tools and still communicate clearly with each other. After attending the Atlassian Summit, I noticed an interesting pattern that was common among some of the people who walked by our booth.

Row Pattern Recognition in SQL

SQL Performance

The ISO/IEC 9075:2016 standard, or SQL:2016 in short, introduces support for a profound concept called Row Pattern Recognition (RPR) in SQL. I posted a suggestion to improve SQL Server by adding support for RPR in T-SQL , but I was quite limited in the space that I had to provide the feedback.

C++ 76

New LUX JavaScript Dashboards

Speed Curve

As organizations work to improve performance for users around the world on slower networks and devices, the focus on JavaScript continues to grow. LUX's new JavaScript dashboards help to identify the problems and solutions for creating a fast, joyous user experience.

Master of web puppets: abusing web browsers for persistent and stealthy computation

The Morning Paper

Master of web puppets: abusing web browsers for persistent and stealthy computation Papadopoulus et al., NDSS’19.

Top 15 Utility Tools for Testers


Recently, we started digging into Reddit, and there we found many very useful threads for testers. While I was going through some of the links, I found this Reddit thread which was talking about tools for testers and I found it pretty interesting, so we decided to make a list for you by compiling all the utility tools for the testers. Let’s have a quick look at this. performance testing software testing qa debugging website testing cross browser testing

Automated Deployment and Architectural Validation with Pitometer and keptn!


Dynatrace news. Validating Deployments still seems to be a semi-automated task for most software delivery teams. Why do I say that?

11 Best Practices for Continuous Performance Testing


To develop a top-notch product, your development teams need to perform continuous performance testing because with it, they can quickly identify key functional bugs as well as those load-handling and performance bugs that are difficult to detect.

Grouped Aggregate Pushdown

SQL Performance

Introduction. In SQL Server 2012, grouped (vector) aggregation was able to use parallel batch-mode execution, but only for the partial (per-thread) aggregate. The associated global aggregate always ran in row mode, after a Repartition Streams exchange.

Measuring Jank and UX

Speed Curve

Ten years ago the network was the biggest problem when it came to making websites fast. Today, CPU is the main concern. This happened because networks got faster while JavaScript moved in the other direction growing 3x in size in the last six years.

Don’t trust the locals: investigating the prevalence of persistent client-side cross-site scripting in the wild

The Morning Paper

Don’t trust the locals: investigating the prevalence of persistent client-side cross-site scripting in the wild Steffens et al., NDSS’19. Does your web application make use of local storage?

7 Reasons Why Unit Tests Are Valuable


With the latest cross-cutting concerns podcast , Matt and I discuss the StackOverflow Developer Survey 2019 results. In the podcast, I mentioned how developers said companies don't implement unit testing but that developers see the value of it. This is good news for the industry: developers see value in unit tests. This survey is proof of that, but there are some developers who still may not see it.

Quickly understand how to improve the above-the-fold user experience of your applications


Dynatrace news. Dynatrace has made it easier for you and your web performance-optimization engineers to access Visually complete metric findings for each page-load that is captured with Dynatrace Real User Monitoring.

The Serif Tax

CSS - Tricks

Fonts are vector. Vector art with more points makes for larger files than vector art with fewer points. Custom fonts are downloaded. So, fonts with less points in their vector art are smaller. That's the theory anyway. Shall we see if there is any merit to it? Open Sans (top) and Garamond (bottom).

How to Perform First Web App Penetration Testing?


In today’s broad digital landscape, web app penetration testing is considered as one of the most important parts of a company’s vulnerability management program. Conducting a web app penetration test not only requires expertise, but it also needs a significant amount of time.

IGNORE_DUP_KEY slower on clustered indexes

SQL Performance

The IGNORE_DUP_KEY option for unique indexes specifies how SQL Server responds to an attempt to INSERT duplicate values: It only applies to tables (not views) and only to inserts. Any insert portion of a MERGE statement ignores any IGNORE_DUP_KEY index setting.