Everything changes and nothing stands still — Overview Old and new versions of the code, and old and new data formats, may potentially all coexist in the system at the same time. In order for the system to continue running smoothly, we need to maintain compatibility in both directions: Backward compatibility: Newer code can read data that was…

All about reading and writing data — Overview This chapter talks about how we can store the data that we’re given, and how we can find it again when we’re asked for it. There is a big difference between storage engines that are optimized for transactional workloads and those that are optimized for analytics. We will talk about…

Using Chef to provision Linux and Windows servers in VMware Sphere — Overview Server provisioning is the process of setting up a server to be used in a network based on the required resources. Provisioning can encompass all of the operations needed to create a new machine and bring it to a working state and includes defining the desired state of the system…

Best practices for developing, testing, and releasing profiles, cookbooks, and policies — Highlights Write InSpec Profiles once and use them everywhere Test-Driven Development using InSpec Profiles Test locally and build/release using CI/CD pipelines Use chef_cookbook_generator to generate the cookbooks and policies Use data bags even with kitchen test Use Azure DevOps as repositories and CI/CD pipelines

A Comprehensive explanation on “solving the finding the longest xyz” coding problem with examples — When we practice solving coding problems, everyone may face problems that ask us to find the longest *** for the given input and logic, many know there are techniques to solve it, after solving quite a few them, I’ like to share what I have learned. General Tips and Techniques Generally, we can use…

A Comprehensive Explanation With Bit Manipulation Examples — 1. Bitwise Operators 1.1 Basic Operations AND ( & ): If both bits in the compared position of the bit patterns are 1, the bit in the resulting bit pattern is 1, otherwise 0. e.g. 5 (101) & 3 (011) = 1 (001). OR ( | ): If both bits in the compared position of the…

Concepts and considerations for some topics in System Design — Table of Contents Concurrency Networking Abstraction Read-world performance and estimation Map-reduce Hadoop and Spark 1. Concurrency 1.1 Threads and processes A thread is a basic unit of CPU utilization. It is also referred to as a “lightweight process”. A process is an instance of a computer program that is being executed. It contains the program code and its current…