Opens in a new windowOpens an external siteOpens an external site in a new window I was recently profiling a production Shopify application server using perf and noticed a fair amount of time being spent in a particular function, st_lookup, which is used by Ruby’s MRI implementation for hash table lookups: Hash tables are used all over MRI, and not just for the Hash object; global variables, insta
![Tuning Ruby's Global Method Cache](https://cdn-ak-scissors.b.st-hatena.com/image/square/6f4e302a4b91f5f51c193c19bcc8ac9facf8704c/height=288;version=1;width=512/https%3A%2F%2Fcdn.shopify.com%2Fs%2Ffiles%2F1%2F0779%2F4361%2Farticles%2Fcoding-on-laptop_4460x4460_2ba0f25e-d153-4cc7-a931-05961430eecc.jpg%3Fv%3D1521214533)