Paul-Henning Kamp, a renowned FreeBSD developer who played a key role in creating systems such as MD5Crypt, Geom, GBDE, and FreeBSD Jail, recently introduced the release of Varnish Cache 8.0. This high-performance caching proxy is designed to operate as an HTTP accelerator. The project, distributed under the BSD license, has been utilized by major platforms like Facebook, Wikimedia, Twitter, Vimeo, Tumblr, New York Times, and Guardian.
Among its distinctive features are the use of EPOLL/KQUEUE, Sendfile, and Madvise system calls. Varnish Cache is capable of handling a throughput of 20 GBPS on standard equipment, accelerating request return by 300-1000 times. The cache is stored in virtual memory, and a notable feature of Varnish is its ability to assemble specific pages on the front end using the esi (edge side includes) language.
Furthermore, Varnish offers a flexible configuration system that allows the use of inserts in the SI. The configuration is done using a special language called VCL, which is compiled into executable binary code. VCL enables users to define the processing of requests, including identifying content, sourcing it, and transforming it before delivery. Additional functionality can be incorporated through various modules, with load balancing mechanisms taking into account server status and response time.
Accompanying the release of the new version, a name change for the project has been announced. Starting from the next release, Varnish Cache will be rebranded as Vinyl Cache due to trademark claims by Varnish Software, a company that supported the development of the open project. The establishment of Varnish Software emerged from LinPro, which was involved in funding the development of Varnish Cache 22 years ago with the backing of the Norwegian newspaper Verdens Gang.