Tag: Cassandra

In this quick blog post, I’m going to assess how the databases that advertise themselves as “Cassandra API-compatible” fare in the compatibility department. But that is all I will do, only API testing, and not an extensive testing, just based…

Overview of Cassandra As previously mentioned in my notes on lightweight transactions, Cassandra does not support ACID transactions. Cassandra was built to support a brisk ingest of writes while being distributed for availability. Follow the link to my previous post…

In this blog, I’m going to give a detailed guide on how to monitor a Cassandra cluster with Prometheus and Grafana. For this, I’m using a new VM which I’m going to call “Monitor VM”. In this blog post, I’m…

Some clients have asked us to change the number of num_tokens as their requirement changes. For example lower number of num_tokens are recommended is using DSE search etc.. The most important thing during this process is that the cluster stays…

Cassandra storage is generally described as a log-structured merge tree (LSM). In general, LSM storage provides great speed in performing writes, updates and deletes over reads. As a general rule, a write in Cassandra is an order of magnitude faster…

A client recently asked us to migrate a Cassandra cluster running in Docker containers to Elassandra, with the data directory persisted via a bind mount. Elassandra is a fork of Cassandra integrated closely with Elasticsearch, to allow for a highly scalable…

DataOps Barcelona is an event organized by Binlogic and will be taking place June 21-22, 2018 in Barcelona, Spain. Pythian is proud to be supporting this inaugural open source-focused conference in Europe! DataOps is of course short for “Database +…

Every now and then I find myself looking for a couple of commands I do often. In some other software/technologies we sometimes find a thing called a “cheatsheet” that displays the more used (and some more obscure commands) of that…

Cassandra nodetool provides several types of commands to manage your Cassandra cluster. See my previous posts for an orientation to Cassandra nodetool and using nodetool to get Cassandra information. My colleague has provided an in-depth analysis of backup strategies in…

Cassandra is a distributed, decentralized, fault-tolerant system. Data is replicated throughout multiple nodes (centers) across various data centers. The fact that Cassandra is decentralized means that it can survive single or even multi-node failures without losing any data. With Cassandra,…