如何同时运行多个 php 文件？

Question

build environment nginx/1.18.0 (Ubuntu 20.04) / php7.4-fpm

i'm confused about php multi-threading capabilities, i know that it doesn't support it in stock build and it requires a PHP build with ZTS (Zend Thread Safety) to go with pthreads or parallel

pthreads seems experimental, unsafe and not fit for server environment so that leaves parallel as for the more suitable option

what i'm trying to accomplish isn't complicated, i just want the server to run a query every second or so looking for new data in a mysql database to serve it through a phpwebsocket without the server halting everything when it starts the query loop because php can't chew gum and walk at the same time.

currently if client 1 loads php page A, he can't access any other pages until page A is done running, yet other clients can still access other pages when client 1 is still running page A which makes me think that it is single threaded per session.

the alternative is having the client side doing it with repeating ajax request, but that seems to be bandwidth wasting and inefficient.

Answer 1

I think you have misunderstood what's happening. You don't need multi-threading to serve multiple web pages at once, and keeping a process running to serve a websocket connection isn't going to make everything else grind to a halt.

currently if client 1 loads php page A, he can't access any other pages until page A is done running, yet other clients can still access other pages when client 1 is still running page A which makes me think that it is single threaded per session.

The word "session" here is probably the key to your actual problem: PHP's session support uses exclusive locking by default. When you call session_start() to load an existing session, the default implementation reads a file on disk, and locks it until the end of the request or until you call session_write_close() . Other attempts to read the same session data will wait until the lock is released. This prevents corruption caused by different requests writing conflicting versions of the same session, but it means that the user will see a delay if they open multiple pages in parallel.

The solution is simple: if you have a long-running request, don't run session_start() , or if you need to read the session, immediately run session_write_close() to unlock it for use by other requests.