So You Want To Remove The GVL? | byroot’s blog

For quite a long time, it has been said that Rails applications are mostly IO-bound, hence Ruby’s GVL isn’t that big of a deal and that has influenced the design of some cornerstone pieces of Ruby infrastructure like Puma and Sidekiq. As I explained in a previous post, I don’t think it’s quite true for most Rails applications. Regardless, the existence of the GVL still requires these threaded systems to use fork(2) in order to exploit all the cores of a server: one process per core. To avoid all this, some people have been calling for the GVL to simply be removed. .