Hi @juliocp87, thanks for reaching out!
Wordfence is unintrusive and generally runs well on the vast majority of ~5m sites it’s installed on despite having to consider many server and plugin/theme combinations. We constantly work on making the plugin faster, perform better, and use less resources but there are not set amounts of RAM, CPU or database queries that we know Wordfence will definitely require in each use-case or hosting environment. Shared hosting, larger databases with more WordPress content, or more installed plugins could all be a factor for performance issues.
Wordfence’s scan does make a lot of database queries as it runs, so is also worth ensuring your max_execution_time is 60 or lower in php.ini, and WP_MEMORY_LIMIT is 256M or higher in wp-config.php. Some ideas around trying different memory limits and our recommendation for execution times are mentioned in our Scan Options and Scan Troubleshooting pages too.
It may also help to set your “Maximum execution time for each scan stage” to 20 in Wordfence > Scan > Manage Scan > Performance Options. Litespeed can experience scan timeout issues unless a configuration change is made. You may not have that but thought it was worth mentioning.
Let us know if your host highlighted something specific from your server/PHP/database logs that might point to Wordfence, as we could make further suggestions based on the precise feedback.
Let us know how you get on,
Peter.
