There are multiple options by now. For one, PHP got a JIT compiler a while ago. That, in combination with the existing opcode cache, actually causes PHP to outperform its interpreted competitors in most cases.
Additionally, there are several application server strategies, sometimes with a process manager that keeps preloaded request workers at hand, sometimes hosting an event loop, and sometimes a request worker that gets partially reset after handling requests. This yields performance comfortably comparable to optimized Node.js apps.
In general, PHP has a highly optimized runtime, and we didn’t even really touch caching yet. Trust me when I say performance is not one of the problems PHP poses :)
And not to forget traditional web server caching. Since they mimick html files on the server, doing your app right, you can use the very mature caching options in the web server / proxies.
Additionally, there are several application server strategies, sometimes with a process manager that keeps preloaded request workers at hand, sometimes hosting an event loop, and sometimes a request worker that gets partially reset after handling requests. This yields performance comfortably comparable to optimized Node.js apps.
In general, PHP has a highly optimized runtime, and we didn’t even really touch caching yet. Trust me when I say performance is not one of the problems PHP poses :)