I have a drupal-based website on a VPS with 1GB RAM and 1Ghz processor share. The webserver is nginx along with php-fastcgi. Currently I am using 10 nginx and 13 php-fastcgi processes. The server load is high most of the times while half of the RAM is unused. The CPU usage rarely reaches 80%.
I have tried some other combinations of nginx/php-fastcgi but am not sure what is the optimal combination because I am quite ignorant about what's going on below the surface. So I appreciate if you could share your experience or give me some clues.