I am configuring a server for a friend.The server has the following specs

8GB RAM 
Quad Core processor 
1 TB HDD 
100 mbps port

However all php files are loadking very slowly.I did a speedtest and server takes 16 secs to Load FIRST byte.I strongly believe its my php-fpm configuration.Server uses nginx and php only , no mysql etc...

My current php-fpm configuration

pm.max_children = 50
pm.start_servers = 10
pm.min_spare_servers = 5
pm.max_spare_servers = 35

Server load and ram usage are perfectly fine

Please suggest me a good configuration for this server

UPDATE: This configuration works fine pm.max_children = 20 pm.start_servers = 7 pm.min_spare_servers = 5 pm.max_spare_servers = 10 pm.max_requests = 100

The problem with first byte load time is solved.However after like 15-20 hours First byte load time increase gradually. I have to reload php-fpm to get small load time Based on my conf above what i modify to it so that first byte load time remain small and i don't have to restart it:P