Book Image

Learning Cassandra for Administrators

By : Vijay Parthasarathy
Book Image

Learning Cassandra for Administrators

By: Vijay Parthasarathy

Overview of this book

<p>Apache Cassandra is a massively scalable open source NoSQL database. Cassandra is perfect for managing large amounts of structured, semi-structured, and unstructured data across multiple data centers and the cloud. Cassandra delivers linear scalability and performance across many commodity servers with no single point of failure.<br /><br />This book starts by explaining how to derive the solution, basic concepts, and CAP theorem. You will learn how to install and configure a Cassandra cluster as well as tune the cluster for performance. After reading the book, you should be able to understand why the system works in a particular way, and you will also be able to find patterns (and/or use cases) and anti-patterns which would potentially cause performance degradation. Furthermore, the book explains how to configure Hadoop, vnodes, multi-DC clusters, enabling trace, enabling various security features, and querying data from Cassandra.<br /><br />Starting with explaining about the trade-offs, we gradually learn about setting up and configuring high performance clusters. This book will help the administrators understand the system better by understanding various components in Cassandra’s architecture and hence be more productive in operating the cluster. This book talks about the use cases and problems, anti-patterns, and potential practical solutions as opposed to raw techniques. You will learn about kernel and JVM tuning parameters that can be adjusted to get the maximum use out of system resources.<br /><br /><br /></p>
Table of Contents (14 chapters)

iostat


This reports CPU and input/output statistics for devices. The iostat command is used for monitoring system input/output device loading by observing the time the devices are active in relation to their average transfer rates. The first report generated by the iostat command provides statistics concerning the time since the system was booted and hence is mostly useless. It is recommended to run it in a loop (using a parameter; for example, iostats –mx 6 9). On multiprocessor systems, CPU statistics are calculated system-wide as averages, and are shown as follows:

The elements of the preceding command line are elaborated in the following table:

Column

Description

tps

Number of transfers (I/O requests) per second for the device.

Blk_read/s

Blocks read per second.

Blk_wrtn/s

Blocks written per second.

Blk_read

Total blocks read.

Blk_wrtn

Total blocks written.

r/s, w/s

The number of read and write requests that were issued to the device per second.

await

The...