TCP: out of memory — consider tuning tcp_mem

Recently we experienced an interesting production problem. This application was running on multiple AWS EC2 instances behind Elastic Load Balancer. The application was running on GNU/Linux OS, Java 8, Tomcat 8 application server. All of sudden one of the application instances became unresponsive. All other application instances were handling the traffic properly. Whenever the HTTP request was sent to this application instance from the browser, we were getting following response to be printed on the browser.

Continue reading “TCP: out of memory — consider tuning tcp_mem”

LARGE OR SMALL MEMORY SIZE FOR MY APP?

Should I be running my application with few instances (i.e. machines) with large memory size or a lot of instances with small memory size? Which strategy is optimal? This question might be confronted often. After building applications for 2 decades, after building JVM performance engineering/troubleshooting tools (GCeasyFastThreadHeapHero), I still don’t know the right answer to this question. At the same time, I believe there is no binary answer to this question as well. In this article, I would like to share my observations and experiences on this topic.

Continue reading “LARGE OR SMALL MEMORY SIZE FOR MY APP?”

Confoo Canada 2019 conference

Confoo montreal is one of the well run, well-attended conference in Canada. This is one of the conferences where they serve 3-course hot lunch meals in a proper dining table with proper silverware :-). Great speakers all around the world, enthusiastic attendees, pleasant ambience (hotel Bonaventure), meticulous organization, beautiful Montreal city – all essential characteristics to make up an excellent conference.

Continue reading “Confoo Canada 2019 conference”

Blog at WordPress.com.

Up ↑