PHP-需要一个用于用户注册的后台站点处理的cron ...（或fork进程）

Question

Whenever a new user signs up on my site, I want to do some pre-processing to shorten their searches in the future. This involves anywhere from 30 to 2 minutes processing time. Obviously I cannot do this when they click the submit button on signup... or on any PHP page they visit. However, I would like this done within 5 minutes of them signing up (or less).

Cron Route I THINK this needs to be in a cron job, and if so, how should I setup the cron job? If so, what should my cron line look like to run every 2 minutes, and how can I insure that I don't have the same cron job overlapping the next?

Event/Fork Route - Preferred If I can possibly throw some event to my server without disrupting my users experience or fork a process off of the users signup (instead of a cron job) how could I do this?

Answer 1

I would recommend neither solution.

Instead, you would be best off with a long running process (daemon) that gets its jobs from a message queue. The message queue itself could be off a database if that is your preferred method.

You will post an identifier for the job to your database, and then a long running process will iterate through them once in a while and act upon them.

This is as simple as:

<?php
while(true) {
   jobs = getListOfJobsFromDatabase();  // get the jobs from the databbase
   foreach (jobs as job) {
      processAJob(job); // do whatever needs to be done for the job
      deleteJobFromDatabase(job); //remember to delete the job once its done!
   }
   sleep(60); // sleep for a while so it doesnt thrash your database when theres nothing to do
}
?>

And just run that script from the command line.

The benefits of this over a cron job are that you wont get a race condition.

You may also want to fork off the actually processing of the jobs so many can be done in parallel, rather than processing sequentially.