Pull to refresh

Development

Show first
Rating limit
Level of difficulty

Top-10 Bugs Found in C# Projects in 2020

Reading time10 min
Views1.3K
image1.png

This tough year, 2020, will soon be over at last, which means it's time to look back at our accomplishments! Over the year, the PVS-Studio team has written quite a number of articles covering a large variety of bugs found in open-source projects with the help of PVS-Studio. This 2020 Top-10 list of bugs in C# projects presents the most interesting specimens. Enjoy the reading!
Read more →

Did It Have to Take So Long to Find a Bug?

Reading time2 min
Views1.8K
image1.png

Have you ever wondered which type of project demonstrates higher code quality – open-source or proprietary? Our blog posts may seem to suggest that bugs tend to concentrate in open-source projects. But that's not quite true. Bugs can be found in any project, no matter the manner of storage. As for the code quality, it tends to be higher in those projects where developers care about and work on it. In this small post, you will learn about a bug that took two years to fix, although it could have been done in just five minutes.
Read more →

Rich text editors from backend perspective

Reading time7 min
Views5K
Welcome everyone, in this article I’m going to overview the most popular types of rich text editors, tradeoffs of their use from a backend perspective. By that I mean:

  • Streaming of content from the rich text editor to other infrastructure tools like full-text search, warehouses, etc.
  • Retrieving of content to clients: mobile, web, desktop.
  • Storing of content in some kind of storage (SQL database in my case)
  • Analyzing of content, which includes point 1, but also analyzing it from the perspective of our application
Read more →

ONLYOFFICE Community Server: how bugs contribute to the emergence of security problems

Reading time12 min
Views964
image1.png

Server-side network applications rarely get the chance to join the ranks of our reviews of errors found in open source software. This is probably due to their popularity. After all, we try to pay attention to the projects that readers themselves offer us. At the same time, servers often perform very important functions, but their performance and benefits remain invisible to most users. So, by chance, the code of ONLYOFFICE Community Server was checked. It turned out to be a very fun review.
Read more →

Big Data Tools EAP 12 Is Out: Experimental Python Support and Search Function in Zeppelin Notebooks

Reading time3 min
Views1.2K

Update 12 of the Big Data Tools plugin for IntelliJ IDEA Ultimate, PyCharm Professional Edition, and DataGrip has been released. You can install it from the JetBrains Plugin Repository or from inside your IDE. The plugin allows you to edit Zeppelin notebooks, upload files to cloud filesystems, and monitor Hadoop and Spark clusters.


In this release, we've added experimental Python support and global search inside Zeppelin notebooks. We’ve also addressed a variety of bugs. Let's talk about the details.


Read more →

Russian microcontroller K1986BK025 based on the RISC-V processor core for smart electricity meters

Reading time10 min
Views7.2K
Welcome to RISC-V era!

Solutions based on the open standard instruction set architecture RISC-V are currently increasing their presence on the market. Microcontrollers from Chinese colleagues are already in serial production; Microchip is offering interesting solutions with FPGA on board. The ecosystem of software and design tools for this architecture are also growing. Seeming previously unshaken leaders have more often found themselves in resale ads, while young startups attract multi-million investments. Milandr also got involved in this race and today began supplying interested companies with samples of its new K1986BK025 microcontroller based on the RISC-V processor core for electricity meters. Well here we go, pictures, characteristics and other information, as well as a little bit of hype under the cut.


Read more →

Big / Bug Data: Analyzing the Apache Flink Source Code

Reading time11 min
Views909
image1.png

Applications used in the field of Big Data process huge amounts of information, and this often happens in real time. Naturally, such applications must be highly reliable so that no error in the code can interfere with data processing. To achieve high reliability, one needs to keep a wary eye on the code quality of projects developed for this area. The PVS-Studio static analyzer is one of the solutions to this problem. Today, the Apache Flink project developed by the Apache Software Foundation, one of the leaders in the Big Data software market, was chosen as a test subject for the analyzer.
Read more →

A Book on the API Design

Reading time1 min
Views1.9K

This year, each of us seeks a special way to pass the time. I am writing a book, for example. A book about one thing I love dearly: the API. (You may read who am I and what expertise got in APIs in my LinkedIn profile.)


I've just finished the first large section dedicated to the API design. You may read it online, or download either pdf or epub version, or take a look at the source code on Github.


The book is distributed for free under a CC-BY-NC license. Enjoy!

Algorithms in Go: Sliding Window Pattern (Part II)

Reading time4 min
Views7.3K

https://s3-us-west-2.amazonaws.com/secure.notion-static.com/adf4f836-dc81-4a3d-8a84-9c1d9c81fd66/algo_-_Starting_Picture.jpg


This is the second part of the article covering the Sliding Window Pattern and its implementation in Go, the first part can be found here.


Let's have a look at the following problem: we have an array of words, and we want to check whether a concatenation of these words is present in the given string. The length of all words is the same, and the concatenation must include all the words without any overlapping. Would it be possible to solve the problem with linear time complexity?


Let's start with string catdogcat and target words cat and dog.


https://s3-us-west-2.amazonaws.com/secure.notion-static.com/a49a78c7-5177-401b-9d30-3f02d3d8db49/algo_-_Input_string.jpg


two concat


How can we handle this problem?

Read more →

The Rules for Data Processing Pipeline Builders

Reading time5 min
Views3.8K


"Come, let us make bricks, and burn them thoroughly."
– legendary builders

You may have noticed by 2020 that data is eating the world. And whenever any reasonable amount of data needs processing, a complicated multi-stage data processing pipeline will be involved.


At Bumble — the parent company operating Badoo and Bumble apps — we apply hundreds of data transforming steps while processing our data sources: a high volume of user-generated events, production databases and external systems. This all adds up to quite a complex system! And just as with any other engineering system, unless carefully maintained, pipelines tend to turn into a house of cards — failing daily, requiring manual data fixes and constant monitoring.


For this reason, I want to share certain good engineering practises with you, ones that make it possible to build scalable data processing pipelines from composable steps. While some engineers understand such rules intuitively, I had to learn them by doing, making mistakes, fixing, sweating and fixing things again…


So behold! I bring you my favourite Rules for Data Processing Pipeline Builders.

Read more →

Development of “YaRyadom” (“I’mNear”) application under the control of Vk Mini Apps. Part 1 .Net Core

Reading time8 min
Views1K
Application is developed in order to help people find their peers who share similar interests and to be able to spend some time doing what you like. The project is currently on the stage of beta-testing in the social network “VKontakte”. Right now I am in the process of fixing bugs and adding everything that is missing. I felt like I could use a bit of destruction and decided to write a little about the development. While I was writing, I decided to divide the text into different parts. Here we are going to pay more attention to backend nuances which I faced, and to everything that a user does not see.
Read more →

Configuring FT4232H using the ftdi_eeprom

Reading time2 min
Views8.2K


The FT4232H is USB 2.0 High speed to UART IC converter. The FT4232H has four UART ports and one USB port.


By connecting EEPROM memory to this chip, you can set specific operating modes or change the manufacturer's data.


Let's look at the example and configure FT4232H directly on a system running GNU/Linux. We will do this using the ftdi_eeprom.

Read more →

Algorithms in Go: Sliding Window Pattern

Reading time3 min
Views5.9K

Let's consider the following problem: we have an array of integers and we need to find out the length of the smallest subarray the sum of which is no less than the target number. If we don't have such a subarray we shall return -1.

We can start with a naive approach and consider every possible subarray in the input:

Continue reading

Playing with Nvidia's New Ampere GPUs and Trying MIG

Reading time11 min
Views4.4K


Every time when the essential question arises, whether to upgrade the cards in the server room or not, I look through similar articles and watch such videos.


Channel with the aforementioned video is very underestimated, but the author does not deal with ML. In general, when analyzing comparisons of accelerators for ML, several things usually catch your eye:


  • The authors usually take into account only the "adequacy" for the market of new cards in the United States;
  • The ratings are far from the people and are made on very standard networks (which is probably good overall) without details;
  • The popular mantra to train more and more gigantic models makes its own adjustments to the comparison;

The answer to the question "which card is better?" is not rocket science: Cards of the 20* series didn't get much popularity, while the 1080 Ti from Avito (Russian craigslist) still are very attractive (and, oddly enough, don't get cheaper, probably for this reason).


All this is fine and dandy and the standard benchmarks are unlikely to lie too much, but recently I learned about the existence of Multi-Instance-GPU technology for A100 video cards and native support for TF32 for Ampere devices and I got the idea to share my experience of the real testing cards on the Ampere architecture (3090 and A100). In this short note, I will try to answer the questions:


  • Is the upgrade to Ampere worth it? (spoiler for the impatient — yes);
  • Are the A100 worth the money (spoiler — in general — no);
  • Are there any cases when the A100 is still interesting (spoiler — yes);
  • Is MIG technology useful (spoiler — yes, but for inference and for very specific cases for training);
Read more →

Russian AI Cup 2020 — a new strategy game for developers

Reading time5 min
Views2.5K


This year, many processes transformed, with traditions and habits being modified. The rhythm of life has changed, and there's more uncertainty and strain. But IT person's soul wants diversity, and many developers have asked us if annual Russian AI Cup will be held this year. Is there going to be an announcement? What is the main theme of the upcoming championship? Should I take a vacation?

Though some changes are expected, it will be held in keeping with the best traditions. In the run-up, we will announce one of today's largest online AI programming championships — Russian AI Cup. We invite you to make history!

Vital Characteristics Of The Best Webflow Designers

Reading time4 min
Views892
A great website serves as the main key to hit success. Enhancing the online presence of your brand is absolutely a must nowadays. Technological advancement has changed the global business landscape. Hence, it is important to have a webflow developer who will take charge of the codes to be used in website templates and designs. Webflow is a website tool. It is a flexible platform that is geared to create a homogenous biz site. The use of this tool will definitely pave the way for your brand to excel on the web.
Read more →

The Code Analyzer is wrong. Long live the Analyzer

Reading time6 min
Views715
Foo(std::move(buffer), line_buffer - buffer.get());

Combining many actions in a single C++ expression is a bad practice, as such code is hard to understand, maintain, and it is easy to make mistakes in it. For example, one can instill a bug by reconciling different actions when evaluating function arguments. We agree with the classic recommendation that code should be simple and clear. Now let's look at an interesting case where the PVS-Studio analyzer is technically wrong, but from a practical point of view, the code should still be changed.
Read more →