Опубликовано

Reverse DevOps, an invitation to project «Bell»

Typical DevOps handles code deploys in a single direction: from Dev to PROD, from lower environments to higher environments, and for this there are many well known solutions like Jenkins, Terraform, Octopus. But in the opposite direction the situation is not so good.

Yes, in many companies there are home-grown processes to copy databases from higher environments to the lower ones (with hiding/removing sensitive data) to reproduce problems, found on PROD. However, in complex scenarios an access to PROD is needed to find the root cause. Developers need at least logs. And in the Enterprise world it’s all depend on the level of paranoya how sensitie the information is.

Thi is what we suggest, the project is to create a safe access method to the higher environments, combining easy friendly interface and interactivity with the full audit of all operations and controlled manner of what users can do and what they can’t. The project is called Bell -Action at a distance, and a bearded guy on the logo is John Steward Bell, you know him if you had ever heard about the Quantum Entanglement.

Read more
Reverse DevOps, an invitation to project «Bell»
Source: habrahabr

Опубликовано

Kernel Queue: The Complete Guide On The Most Essential Technology For High-Performance I/O

When talking about high-performance software we probably think of server software (such as nginx) which processes millions requests from thousands clients in parallel. Surely, what makes server software work so fast is high-end CPU running with huge amount of memory and a very fast network link. But even then, the software must utilize these hardware resources at maximum efficiency level, otherwise it will end up wasting the most of the valuable CPU power for unnecessary kernel-user context switching or while waiting for slow I/O operations to complete.

Thankfully, the Operating Systems have a solution to this problem, and it’s called kernel event queue. Server software and OS kernel use this mechanism together to achieve minimum latency and maximum scalability (when serving a very large number of clients in parallel). In this article we are going to talk about FreeBSD, macOS and kqueue, Linux and epoll, Windows and I/O Completion Ports. They all have their similarities and differences which we’re going to discuss here. The goal of this article is for you to understand the whole mechanism behind kernel queues and to understand how to work with each API.

Read more
Kernel Queue: The Complete Guide On The Most Essential Technology For High-Performance I/O
Source: habrahabr

Опубликовано

[Translation] Японский дизайн — больше, чем минимализм

Проблема, с которой я, как дизайнер презентаций, сталкиваюсь чаще всего, — это необходимость втиснуть большой объем информации на минимальное количество слайдов (так хочет клиент) и при этом разместить информацию эстетически привлекательно.

«Это невозможно» — думаю я, переставляя текстовые блоки, словно игрок в Тетрис. Но внезапно мне приходит мысль, что именно в этом преуспели японцы. Просто взгляните на их меню, на их журналы, брошюры или даже на улицы японских городов. 

Тем не менее, когда я ищу в Гугле словосочетание «японский дизайн», всё, что мне выдает поисковик, — это статьи про минимализм в сочетании с фото симметричных садов камней, чайных чашек нейтральных тонов и деревянных интерьеров, в которых могла бы, кажется, жить Мари Кондо.

Почему лишь такой подход является синонимом японского дизайна, если мы говорим о стране, известной одновременно магазинами MUJI и Don Don Donki, дзен-садами и хаотичной рекламой?

Читать далее
[Translation] Японский дизайн — больше, чем минимализм
Source: habrahabr