PHP memory consumption with Arrays and Objects (update: HHVM, phpng June-2014)

Lessons learned: PHPng is significantly faster and uses significantly less memoryobjects need more memory than arrays (+ 5-250 percent)if array values are numeric, don't save them as strings!saving 1M integers takes 33M of memory with PHPng (increase by factor 8)saving 1M integers as strings takes 79M of memory with PHPng (increase by factor 20)using SplFixedArray can reduce memory usage by 20-100