PHP使用冗长的循环创建不稳定的服务器错误

Question

I have a PHP script that pulls down a bunch of RSS feeds. To prevent overloading the publishers' servers, I use the PHP Sleep function to slow things down.

The entire script could last for a couple of hours.

If I run this from a Cron job on GoDaddy, it will happily work for 5 - 10 minutes and then return a server error. I checked and the PHP maximum execution time is 30 seconds, so I'm not sure if this is the cause of the problem.

If I run the job on my Mac, my local PHP also has a default maximum execution time of 30 seconds, but this script does work if I run it from the terminal, but I don't understand why.

How do I loop a script that will exceed 30 seconds without running into unreliability problems?

Help appreciated.

Answer 1

Short answer is use set_time_limit(0) to allow for a long-running script. Your terminal (CLI) PHP probably has it set to 0. You could also be running out of memory, especially on PHP 5.2 or older. Log all errors to a file, and inspect it.

You could rewrite your program to be able to work on a subset of the data during one run. The benefit of that approach is you could use it to run 24/7 or to run every five minutes, depending on what the PHP environment supports. You could also run multiple instances at a time, each working on their own data.