Maximum number of database connections
Introduction Have you ever wondered what the maximum number of database connections provided by a given RDBMS is? In this article, we are going to see what limits the number of database connections, no matter if you’re using Oracle, SQL Server, PostgreSQL, or MySQL.
Java Performance Workshop with Peter Lawrey
Peter Lawrey at IT Days I’ve just come back from a Java Performance Workshop held by Peter Lawrey at Cluj-Napoca IT Days. Peter Lawrey is a well-known Java StackOverflow user and the creator of Java Chronicle open-source library. Of Java and low latency Little’s Law defines concurrency as: To increase throughput we can either: increase server resources (scaling vertically or horizontally) decrease latency (improve performance) While enterprise applications are usually designed for scaling, trading systems focus on lowering latencies. As surprising as it may sound, most trading systems, I’ve heard of, are… Read More
The simple scalability equation
Queuing Theory The queueing theory allows us to predict queue lengths and waiting times, which is of paramount importance for capacity planning. For an architect, this is a very handy tool since queues are not just the appanage of messaging systems. To avoid system over loading we use throttling. Whenever the number of incoming requests surpasses the available resources, we basically have two options: discarding all overflowing traffic, therefore decreasing availability queuing requests and wait (for as long as a time out threshold) for busy resources to become available This behavior applies… Read More