The server runs XAMPP (Apache and MySQL mainly). Lately the concurrent user count has increased, and the server crawls and sputters during peak load. It only has 4GB RAM though. So, my question is will increasing RAM make a difference?
Increasing MySQL max connection has a direct effect on RAM, as it increases the number of file descriptors that mysqld requires
max_connections = (Available RAM - Global Buffers) / Thread Buffers
To get the global and thread buffers
SHOW VARIABLES LIKE '%buffer%';
Just have a look in the number of opened tables
mysqladmin status SHOW GLOBAL STATUS LIKE 'Opened_tables';
Note: It is always better to have separate servers for Apache and MySQL. Increasing RAM will definitely help