Unrelated and Unusual Note: I am devastated seeing India’s helpless COVID-19 second wave situation due to severe Oxygen, medical equipment supply shortage and broken supply chain. I have been in a dilemma whether to publish any article at all since so many people are posting all around to seek help…

Setting The Context The first article of this series discussed physical time, the second article discussed logical time predominantly vector clock and version vectors, the third article mostly discussed Google True Time and related systems in detail. By now, we know the following points: Using a centralized clock in a distributed system is…

In our last article, we looked into logical clocks especially vector clocks and version vectors deeply and analyzed how they are very useful in real life for designing eventually consistent systems like Riak or Amazon Dynamo DB. But not every eventually consistent systems use vector clock. How Cassandra Handles Ordering Cassandra is a NoSQL…

Setting The Context In the previous article, we talked about physical clocks in detail, we discussed that in most of the use cases, for a high scale system, using physical clock time is not the right choice unless the time difference across the nodes in a cluster is bounded by an extreme tight…

Introduction As a human being, we take birth as a child ( 0th year), start going to school ( ~ 5th year ), university for under graduation ( ~ 18th year ), possibly post-graduation ( ~ 22nd year ), then start our career ( ~ 22nd to 24+ year ) and…

Note: On October 04, 2017, I published a small article on redis hash table internals. But I think, there are lot more details to cover on redis dictionary topic. Hence as an extension to the previous one, I decided to write this new article which is more comprehensive. Redis is…

We discussed Raft replication in details in part 2 of this series. That becomes prerequisite for this article. Please head over to part 2 if you haven’t already. We’ll simulate some scenarios in this article and see how Raft behaves in such cases. …

In the part 1 of this series, we got the basics of Raft. Please go through that part first if you have not already. In this part, we’ll concentrate on detailed Raft replication technique. The concepts explained here are very important & core to Raft. Raft Replication The core idea behind any…

The goal of The Series There are many articles on Raft however most of them are short, theoretical, and not detailed. Consensus algorithms is an area where shortcut analysis does not work as the topic is pretty hard to understand. …