W3 Total Cache generally works fine. I use it with memcached and PHP's new built-in caching module (replacement for APC) and get my site blitzed from time to time due to major mentions in the media with few problems. SSD on Digital Ocean probably helps with disk caching too.
I use Apache but falcolas' point of nginx (often in combination with Varnish and potentially hhvm; I've used this combo before with great success) is worth considering as well.
No replacement for good configuration of your database (try MySQLtuner.pl if you use MySQL/MariaDB) of course.
I use Apache but falcolas' point of nginx (often in combination with Varnish and potentially hhvm; I've used this combo before with great success) is worth considering as well.
No replacement for good configuration of your database (try MySQLtuner.pl if you use MySQL/MariaDB) of course.