Write up Performance Guide for JS Best Practices

[dignifiedquire]

• https://github.com/mraleph/irhydra
• node --prof and node --prof-process
• Chrome JavaScript profile
• asm.js http://asmjs.org/
• benchmark.js
• measure, measure, measure
• hot code paths
• the fastest code is the one that doesn't run
  • early exits
  • reuse variables to avoid memory allocations
• Types are important
  • arrays
    • fixed sized arrays are better than growing & shrinking
    • all elements in an array should be of the same type (ideal 32 bit ints)
  • initialise variables with the correct type
  • avoid using objects
  • don't resize buffers

[daviddias]

@dignifiedquire 🙏🏽