CentOS – Remove Swap safely

If the default installation has swap on, you will see it from block device list: Many installations require swap to be off for performance reasons (although some advocate turning off swappiness of the application, instead of removing swap partition from operating system, which is a separate topic). This can be turned off by a simple … Read moreCentOS – Remove Swap safely

Cassandra Architecture Summary

Disclaimer: many contents here are from Cassandra The Definitive Guide Gossip and Failure Detection Cassandra uses a gossip protocol that allows each node to keep track of state information about the other nodes in the cluster. The gossiper runs every second on a timer. Gossip protocols assumes a faulty network, are commonly commonly employed in … Read moreCassandra Architecture Summary

TCPdump and Wireshark configuration

This article explains how to troubleshoot TCP packet from Linux (CentOS) and Windows with TCP dump and wireshark. Both are important tools for troubleshooting. If you are troubleshooting a Windows server and have access to it to install Wireshark then there is nothing to worry about. Even if the server to troubleshoot is a Linux … Read moreTCPdump and Wireshark configuration

The Digital Doctor: Hope, Hype, and Harm at the Dawn of Medicine’s Computer Age

Reading notes: In healthcare, radiology is a successful sub-field that went digital without federal incentives, with a minimum of fuss and bother, and about a decade before the rest of healthcare did. Radiology’s experience over the past 15 years offers a crystal ball for the rest of the healthcare system. The speed with which computerization … Read moreThe Digital Doctor: Hope, Hype, and Harm at the Dawn of Medicine’s Computer Age