GPLScale - a GPL fork of MaxScale by MariaDB Corporation (now under BSL license)
The GPLScale is an intelligent proxy that allows forwarding of database statements to one or more database servers using complex rules, a semantic understanding of the database statements and the roles of the various servers within the backend cluster of databases.
GPLScale is designed to provide load balancing and high availability functionality transparently to the applications. In addition it provides a highly scalable and flexible architecture, with plugin components to support different protocols and routing decisions.
GPLScale is implemented in C and makes extensive use of the asynchronous I/O capabilities of the Linux operating system. The epoll system is used to provide the event driven framework for the input and output via sockets.
The protocols are implemented as external shared object modules which can be loaded at runtime. These modules support a fixed interface, communicating the entries points via a structure consisting of a set of function pointers. This structure is called the "module object".
The code that routes the queries to the database servers is also loaded as external shared objects and are referred to as routing modules.
Bugs can be reported in the GitHub issue tracker.
For information about installing and using GPLScale, please refer to the documentation. It is in Markdown format.
You can point your browser to the GPLScale project at GitHub. Look inside the "Documentation" directory, where you will find a file named Documentation-Contents.md. Click on that, and GitHub will show the documentation in its intended display format. The contents page lists the available documents and has links to them.
If you do not want to rely on the internet, then clone the project from GitHub and point your browser to the Documentation-Contents.md file in your local file system and proceed as above.