My PHP application needs to send product expiry notifications to customers everyday. I am thinking of:
A one-time cron job for a php script that identifies the customers from a table of 10000 rows then send an email to each one using the SwiftMailer library. Each email will have unique content so I am not planning to do "batch send". *Con: * Too slow and the server may kill it.
A recurring five-minute cron job that would send a definite number of emails (eg. 20) for every execution. *Con: * All customers may not receive emails since the the queue may not finish within 24 hours.
Please give alternatives and suggestions. TIA.