Lalita Kc

Understanding the Three-Phase Commit (3PC) Protocol in Distributed Systems

- March 28, 2020

In modern software engineering, distributed database systems and microservices need a way to ensure data consistency across multiple servers. If a user makes a transaction, it must either succeed everywhere or fail everywhere. This is where commit protocols come into play. While the Two-Phase Commit (2PC) protocol is widely known, it suffers from a major flaw: blocking . If the coordinator node crashes, the participating nodes can get stuck indefinitely waiting for instructions. To solve this, the Three-Phase Commit (3PC) Protocol introduces an extra step to remove this blocking vulnerability. Here is how it works . The Three Phases of 3PC The protocol is divided into three distinct steps managed by a central "Coordinator" communicating with multiple "Cohorts" (participants). 1. Phase One: CanCommit (Voting Phase) The Coordinator sends a CanCommit query to all cohorts asking if they are ready to process a transaction. If a cohort is ready, it replies with a Yes ...

Mastering Java Pattern Programs: Star Pyramids and Triangles Explained

- December 08, 2020

Pattern printing programs are a staple in university computer science exams and junior software engineering interviews. While they might seem like a simple visual trick, pattern programs are actually an excellent way to test a developer's understanding of nested loops and coordinate logic. If you can master pattern printing, you will have a much easier time understanding how to traverse 2D arrays and matrices later in your career. Below, we break down how to print the most common star ( * ) patterns in Java. You can easily swap the star for a number or character depending on your requirements. 1. The Pyramid Star Pattern The Logic: To print a centered pyramid, we need one outer loop and two inner loops. The Outer Loop: Controls the number of rows. The first inner loop prints decreasing spaces before the stars to center them . The Second Inner Loop: Prints the stars with a space after each one. The Code: public class Main { public static void main(String[] a...

How beautiful is Nepal? 12 Most Beautiful Places On Nepal

- April 08, 2019

Nepal, The Most Beautiful Country !!! Nepal is a beautiful nature blessed country in the world. It is located in South Asia between the two largest countries India and China. The main beauty of this country is we can feel really a piece of heaven on there Natural places. So, The Most Beautiful Places On Nepal Are: Everest Base Camp Everest Base Camp is the beautiful heaven located in highest pick on earth at Khumbu Region of Nepal. Historically, it is the most famous trekking place of pride, glory and tragedy as well. Most Importantly, it is the gateway of all the Mt. Everest climbers. So, it is totally a exciting, challenging and thrilling world class high Himalayas trekking journey. Trekking on Everest Base Camp will be the most beautiful life time experience. You can observe the best pictorial Khumbu valley, along with, the best view points on earth like Kala Patthar(5555m height), beautiful pick view of Mt. Everest(8848.86m height ) and nearby mountains too. Lumbini Siddhartha G...