For those of you interested in parallelism in browsers, I suggest you keep an eye on Mozilla's experimental new browser engine, Servo.[1] The goal is to make use of a variety of concurrency strategies (such as a Chrome-esque process-per-tab design[2]) and Rust's built-in support for memory-safe concurrency abstractions (fork/join, lightweight tasks, SIMD, etc.) to produce a ludicrously parallel[3] web browser. And even if Servo itself never happens to make its way into production, one of its purposes is to enable Mozilla to explore effective parallelism strategies to pursue with Gecko.
[2] I wasn't exactly thrilled about this myself, but as long as Servo has to interact with C++ code (notably, SpiderMonkey) this was judged critical for security. Fortunately, pcwalton seems to believe that Servo's tab processes will occupy less memory than Chrome's.
[1] https://github.com/mozilla/servo/
[2] I wasn't exactly thrilled about this myself, but as long as Servo has to interact with C++ code (notably, SpiderMonkey) this was judged critical for security. Fortunately, pcwalton seems to believe that Servo's tab processes will occupy less memory than Chrome's.
[3] https://github.com/mozilla/servo/wiki/Design