Products Cache:
CRON job Only:Choose whether the cache should be updated only when called via CRON. Disable this to process on every page load.The CRON is the time-based job scheduler used to schedule the jobs to run periodically at fixed times, dates or intervals.
CRON key: When you have enable ‘CRON Job Only’ above.Then you must pass a CRON key to validate CRON calls. Empty CRON key is not allowed. The CRON is the time-based job scheduler used to schedule the jobs to run periodically at fixed times, dates or intervals.