I have a PHP cron job running late at night to generate PDF payslips with TCPDF and place them in a folder on the server. It has worked fine all along, but I recently migrated to a new server and now it simply stops processing after about 15 seconds. There is nothing in the Apache error logs, which tells me it is not generating an error.

It would normally take a few minutes to generate more than 2,500 PDFs, but now it creates just under 300 in the 15 seconds before simply stopping at a non-logical place. Server timeouts are set correctly, and there is nothing overriding them.

It simply stops processing after 15 seconds with no warning or error message or error log entry. Could it be a memory issue?

Any ideas?

I tried doubling the PHP memory limit, hoping that it would generate at least some extra PDFs, but the 15 seconds remain consistent.