Apache Traffic Server vs Caffeine

Apache Traffic Server is a free, open-source caching proxy server for HTTP/1.1 and HTTP/2. It stores frequently requested pages, images, and web service calls so they can be reused, with the stated aims of improving response time and reducing server load and bandwidth needs. It can also add keep-alive behavior, filter or anonymize requests, and balance traffic through a proxy layer. Deployment patterns include web proxy cache, reverse proxy, and cache hierarchy. As a layer 7 HTTP load balancer, it can choose next-hop servers using request attributes, weighted round robin, or URL consistent hashing. Plug-in APIs let teams add behavior such as changing headers, handling ESI requests, or implementing cache algorithms. Security options include client access controls and authentication, SSL termination, and SSL-based access control. It is self-hosted, with Linux and macOS listed as platforms. The project identifies enterprises, internet service providers, backbone providers, and large intranets as its intended audience. The listed stable release is 10.2.0; 9.2.15 is listed as the long-term support release.

Caffeine is a free, open-source in-memory caching library for Java, distributed under the Apache License, Version 2.0. It provides an API inspired by Google Guava and can load entries automatically, including asynchronously. Size-based eviction uses configured limits with frequency and recency, while entries can expire according to time since their last access or write. When a stale entry is first requested, Caffeine can refresh it asynchronously. Other functions include weak keys, weak or soft values, removal notifications, writes to external resources, and cache statistics. The project offers JSR-107 JCache, Guava adapters, and a simulation extension, with community integrations listed for Spring Cache, Play Framework, Micronaut, Quarkus, and Apache Camel. The project directs users to Maven Central and provides Gradle coordinates for the core library and optional extensions. Version 3.x is intended for Java 11 or newer; earlier Java versions use 2.x. Maven Central artifacts are accompanied by GPG and Sigstore signature files according to the security policy.