Ruby gvl-improvement at ruby 1.9.3The document discusses Ruby's Global VM Lock (GVL) and improvements made in Ruby version 1.9.3. The GVL ensures only one Ruby thread can execute at a time, limiting Ruby's ability to take advantage of multi-core CPUs. Ruby 1.9.3 improves threading performance by releasing the GVL during I/O operations, allowing other threads to run while one thread is blocked on I/O. It also uses POSIX sched_yield
