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The Physalia configuration store for chain replication of EBS is implemented as key-value stores maintained over a large number of these cells. They built a test harness, called SimWorld, which abstracts networking, performance, and other systems concepts. The goal of this approach is to allow developers to write distributed systems tests, including tests that simulate packet loss, server failures, corruption, and other failure cases, as unit tests in the same language as the system itself.

Almost all of the billions of devices connected to the internet have onboard clocks, which need to be accurate to properly perform their functions. Many clocks contain inaccurate internal oscillators, which can cause seconds of inaccuracy per day and need to be periodically corrected. Incorrect time can lead to issues, such as missing an important reminder or failing a spacecraft launch.

NASA needs 215 more petabytes of storage by the year 2025, and expects Amazon Web Services to provide the bulk of that capacity. However, the space agency didn’t realize this would cost it plenty in cloud egress charges. As in, it will have to pay as scientists download its data.

Hi! I’m one of Embox RTOS developers, and in this article I’ll tell you about one of the typical problems in the world of embedded systems and how we were solving it. Control and responsibility is a key point for a wide range of embedded systems. On the one hand, sensors and detectors must notify some other devices that some event occurred, on the other hand, other systems should react as soon as possible. Examples of such systems include CNC, vehicle control, avionics, distributed sensor systems and lot of others. At the same time, it’s really hard to develop bare-metal programs for a number of reasons: Developers don’t have much choice for frameworks and languages: it probably will be ANSI C and assembly language even for non-time-critical parts of code which can be developed faster with something else (for example, debugging output, collecting statistics, some user interface for diagnostics and so on)

The company is expanding its US network in a big way, and it’s turned to two edge data center startups for help. In January, Cloudflare, which helps companies make their web services run faster and be more secure – and which more recently started to use its global data center network to also provide cloud computing services – said it would expand the network in the US with three dozen new locations. Shortly thereafter, the company said it would add even more locations in the US – about the same amount as in the first announcement.

There may be an undiscovered tribe deep in some jungle somewhere that hasn’t made up their mind on microservices, but I doubt it. People love microservices or love to hate microservices. There’s not much in between. So it means something when even a team at a company like Uber announces a change away from microservices to something else. What? Macroservices.

In this post, we’re going to take a deeper dive into the Postgres and PostGIS internals to find out how this actually works. By the time we surface you will have a better understanding of the advanced technical capabilities and unparalleled extensibility of Postgres. You’ll also appreciate how the open philosophy of Postgres has fostered a development community whose collaboration over many years has provided powerful features that benefit numerous users.

Executing a full rewrite of the Dropbox sync engine was pretty daunting. (Read more about our goals and how we made the decision in our previous post here.) Doing so meant taking the engine that powers Dropbox on hundreds of millions of user’s machines and swapping it out mid-flight. To pull this off, we knew we would need a serious investment in automated testing. Our testing strategy gave us confidence that we were on the right track throughout the rewrite, and today it allows us to continue building and shipping new features on a quick release cycle. First, we’ll discuss the types of testability considerations that went into the design of Nucleus, our new sync engine, and then we’ll get into some of the randomized testing systems that we built on top of our test-friendly architecture.

A passenger opens the app, requests a ride, and just a few minutes later there is a car with a friendly driver in front of them. They may know this driver went through a background check and other vetting; however, many might not realize all the complexity in the on-boarding process. Driver and vehicle requirements vary substantially across markets (and even at very proximate locations) due to varying market dynamics and government regulations.

Spotify built its business on flawless content delivery. Our streaming platform serves up more than 50 million tracks (plus an array of images and other assets) to more than 230 million monthly active users around the world — making us one of the world’s leading streaming services. With content that feels instant and immersive, we help our customers have the best experience possible with their favorite artists.