• Reliable load testing with regards to unexpected nuances

      We thought about building the infrastructure for large load tests a year ago when we reached the mark of 12,000 simultaneously active online users. In three months, we made the first version of the test, which showed us the limits of the service.

      The irony is that simultaneously with the launch of the test, we reached the limits on the production server, resulting in two-hour service downtime. This further encouraged us to move from making occasional tests to establishing an effective load testing infrastructure. By infrastructure, I mean all tools for working with load testing: tools for launching the test (manual and automatic), the cluster that creates the load, a production-like cluster, metrics and reporting services, scaling services, and the code to manage it all.

      image

      Simplified, this is what our structure looks like: a collection of different servers that somehow interact with each other, each server performing specific tasks. It seemed that to build the load testing infrastructure, it was enough for us to make this diagram, take account of all interactions, and start creating test cases for each block one by one.

      This approach is right, but it would have taken many months, which was not suitable for us because of our rapid growth — over the past twelve months, we have grown from 12,000 to 100,000 simultaneously active online users. Also, we didn’t know how our service infrastructure would respond to the increased load: which blocks would become the bottleneck, and which would scale linearly?
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    • Scientists Turn a Quantum Computer into a Time Machine — At least, for a Second…

        Scientists said they were able to return the state of a quantum computer a fraction of a second into the past, according to a university press release. The researchers, who are from the Moscow Institute of Physics and Technology, along with colleagues from the U.S. and Switzerland, also calculated the probability that an electron in empty interstellar space will spontaneously travel back into its recent past. The study came out recently in Scientific Reports.
        “This is one in a series of papers on the possibility of violating the second law of thermodynamics. That law is closely related to the notion of the arrow of time that posits the one-way direction of time: from the past to the future,” commented the study’s lead author Gordey Lesovik, who heads the Laboratory of the Physics of Quantum Information Technology at MIPT.

        While the researchers don’t expect you to take a trip back to the high school prom just yet, they added that the time reversal algorithm could prove useful for making quantum computers more precise.

        “Our algorithm could be updated and used to test programs written for quantum computers and eliminate noise and errors,” Lebedev explained.

        The researchers said that the work builds on some earlier work that recently garnered headlines.

        “We began by describing a so-called local perpetual motion machine of the second kind. Then, in December, we published a paper that discusses the violation of the second law via a device called a Maxwell’s demon,” Lesovik said. “The most recent paper approaches the same problem from a third angle: We have artificially created a state that evolves in a direction opposite to that of the thermodynamic arrow of time.”
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      • Research in rejuvenation biotechnology – where are we now?



          Certainly this event is an example of some of the people in our longevity community coming in and just taking over a little bit of somebody else's conference to talk about longevity… but really exposing the rest of the community to it. I'm finding that at every event I go to, I'd really love to have conference presentations where I get to talk about some interesting thing about the longevity industry, because there are a lot of really interesting things going on.

          But every presentation turns out to be «hey, we exist, please notice us — because this is really, really important.» Everything that you guys think that you are doing in medicine is about to be up-ended, because suddenly we're going to be actually able to stop people from getting sick and incapacitated and debilitated in old age. This is happening right now, the first rejuvenation therapies exist. But nobody notices.
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        • Simple and free video conferencing

            Due to a rapid increase in remote work, we have decided to offer video conferencing. Like most of our services, it is free of charge. It is built on a reliable open-source solution, it is mostly based on WebRTC, which allows communicating in the browser by just clicking on a link. Below we’ll tell you more about its features and some of the problems we’ve run into.


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          • Custom Shopify Automation for Your Business

              E-commerce today has become so frequent that it has become almost a standard chain of stores, where most people make purchases. But even online stores are trying to save money by becoming drop shippers and more working on additional implementations, rather than on the maintenance and payment of huge storage spaces.

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            • Safe-enough linux server, a quick security tuning

              The case: You fire up a professionally prepared Linux image at a cloud platform provider (Amazon, DO, Google, Azure, etc.) and it will run a kind of production level service moderately exposed to hacking attacks (non-targeted, non-advanced threats).

              What would be the standard quick security related tuning to configure before you install the meat?


              release: 2005, Ubuntu + CentOS (supposed to work with Amazon Linux, Fedora, Debian, RHEL as well)


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            • AdBlock has stolen the banner, but banners are not teeth — they will be back

              More
              Ads
            • Windows Native Applications and Acronis Active Restore

              • Translation
              We continue telling you about our cooperation with Innopolis University guys to develop Active Restore technology. It will allow users to start working as soon as possible after a failure. Today, we will talk about Native Windows applications, including details on their development and launch. Under the cut, you will find some information about our project, and a hands-on guide on developing native apps.

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            • 14 Successful Ways to Use Live Video Streaming for Business in 2020

                Live streaming is engaging precisely because it is so easy to access. All one needs to tune in is a screen, an internet connection and access to streaming sites. Today, business live streaming has been incorporated into media-heavy platforms like YouTube, Facebook and Instagram. However, the best way to live stream, and how to use live streams for business, depend on your product and business goals.

                "

                New to the live streaming game? It’s a great time to test the waters and figure out how to live stream a business, now that a majority of the population is more hooked to their social media platforms than ever before. Here are the best ways to live stream a business that are also engaging, informative and business-goal-oriented.

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              • C# and .NET tricky questions



                  I have collected some most interesting and not well-known questions from the web. And also based on interesting books, articles and videos I have seen, I have wrote some of questions myself.
                  I want propose you to guess right answer.
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                • The disinfection gateway with temperature meter and antiseptic

                  • Translation
                  Hello! First of all, thanks for the warm reviews and interesting comments on my first post about the alarm system for the "Zaporozhets". This is very motivating to continue to share with my work.
                  This time I want to tell you about the design of the disinfection gateway, which I had to do in just two nights.



                  I work as an industrial designer at Tabula Sense Company and design furniture with the integrated electronics most of the time. However, considering everything that is happening, our management thought about how to connect the available resources to the fight against the pandemic.
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                • MEMS accelerometers, magnetometers and orientation angles

                  • Translation


                  When it's necessary to evaluate the orientation angles of an object you may have the question — which MEMS sensor to choose. Sensors manufacturers provide a great amount of different parameters and it may be hard to understand if the sensor fit your needs.

                  Brief: this article is the description of the Octave/Matlab script which allows to estimate the orientation angles evaluation errors, derived from MEMS accelerometers and magnetometers measurements. The input data for the script are datasheet parameters for the sensors. Article can be useful for those who start using MEMS sensors in their devices. You can find the project on GitHub.
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                • The World’s Top 12 Quantum Computing Research Universities

                  In just a few years, quantum computing and quantum information theory has gone from a fringe subject offered in small classes at odd hours in the corner of the physics building annex to a full complement of classes in well-funded programs being held at quantum centers and institutes at leading universities.

                  The question now for many would-be quantum computer students is not, “Are there universities that even offer classes in quantum computing,” but, rather, “Which universities are leaders at quantum computing research.”

                  We’ll look at some of the best right now:

                  The Institute for Quantum Computing — University of Waterloo


                  The University of Waterloo can proudly declare that, while many universities avoided offering quantum computing classes like cat adoption agencies avoided adoption applications from the Schrodinger family, this Canadian university went all in.

                  And it paid off.
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                • Featureban Online: The Facilitator Guide

                  • Translation
                  When you want to introduce some new methods or ideas, there is nothing better than hands-on experience. People usually think games and having fun don’t go together with some serious work. But in the Agile world, using games to explore and teach new concepts is common. For teaching Kanban, there are several simulation games widely used in classes. Most popular are Featureban, Flowlab, and getKanban.



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                • The snail terrarium concept

                  • Translation
                  Hello everybody! Today I want to share with you the concept of a rather unusual device, which, like the alarm remote for the "ZAZ Zaporozhets", was developed exclusively for creative purposes, without the further implementation.



                  It all started with the fact that two of the three grape snails escaped from our director's terrarium, and the third one died suddenly without lasting even three days. Obviously, the blame for this situation was putted not on the inability to keep the mollusk and irresponsibility, but on the “terrible terrarium”.
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                • Service for Active Restore or the Story of an Industrial Project at Innopolis

                  • Translation
                  Hello, Habr! My name is Roman. Today I would like to share a story of how we at Innopolis University developed a test stand and a service for Acronis Active Restore system, which will soon become part of the company’s product range. Those interested to know how the University builds its relationship with industrial partners are welcome to click the «Read More» button.

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                • The concept of a car alarm remote for «ZAZ Zaporozhets»

                  • Translation
                  Hello friends! My name is Ruslan Mazur, I am an industrial designer. In my free time I like to invent and visualize devices that are not designed for production, but allow you to do creativity. Regardless of the technical difficulties, the cost of the product and so on.

                  For three years now I have been working at Tabula Sense Company and most of the time I have been developing various furniture with built-in electronics.



                  Today I want to share with you the concept of a car alarm remote control for ZAZ Zaporozhets (or Fiat 600, whatever suits you best), as if the similar devices already existed in those days.
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                • How I fix cups-printing in Buildroot

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                    Intro


                    Like I said earlier in previos articles, Buildroot is a great system for embedded Linux development. But sometimes strange things can happen.


                    Once upon a workday, I got the following task: add printing system in firmware (Kraftway terminal Linux next generation). Ok, so I had to add cups + cups filter and to build firmware. I set a postscript-printer and got an error "Filter failed". Trivial tasks turned into serious work.


                    In this article, I wrote my own way of solving this problem. It may be useful for other developers and IT-specialist and, also, for a deeper understanding of the Buildroot.


                    If you are a Buildroot beginner, I recommend reading my previous articles.


                    Update 1 may 2020


                    Revisioned versions of this patches applied to master.

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