Question

I have a PHP script that needs to run some pretty hefty imagemagick commands.

These commands may be run at the same time by multiple users, so user a, b, c, and d would all be running the same task. I want to make it into a background process, so I can use jQuery, for example, to show a loading bar during processing.

What would be the best way to accomplish this? Or, is there another method that may be easier?

Answer 1

There are quite some guides how to create Deamons with PHP:
http://kevin.vanzonneveld.net/techblog/article/create_daemons_in_php/

Or how to background a process:
http://waynepan.com/2007/10/11/how-to-use-ignore_user_abort-to-do-process-out-of-band/

You could create a deamon running in the background, reading from a database table that contains all jobs that need to be worked on and then you can check with your frontend process for that table every once in a while until all jobs have cleared for that specific process.

You can also use a message queue for that, so you can use multiple deamons in parallel (for example on multicore systems) without conflicting.