We’d like to host about 50 WP sites with low traffic (I mean really low, under 100-1000 visits per day for all sites in total, excluding search engine robots).

We use WordPress 5.4, php7-fpm, Nginx and external MySQL database.

Please suggest what CPU Cores numbers and RAM size would be enough for this configuration.

NB: Sometimes we observe high CPU usage of php-fpm on our 2 Cores / 4 Gb RAM instance, hope it could be tweaked, so we could use instance with less cores/RAM.