This is a small note about programming highload backend applications.
I perform some test for DataBase and PHP programming techniques and found solution work at 4 times faster and economy.
MyISAM vs InnoDB
After some alter tables performs I found InnoDB MySQL DataBase engine in 10 times faster than MyISAM.
Object oriented code paradigm vs Array oriented code style
Yes. This solutions tested to. Array oriented code style faster at 4 times and uses less server RAM than Object oriented programming technique. Also paradoxically interested moment is a needles of OpCache, MemCache and XCache solutions when you coding in Arrays. Time of execution script to drop PHP process with OpCache when you use Arrays instead of Objects in 10 times bigger than not use OpCache.
This is 2 primary thing you need to keep in mind when build large HighLoad server applications. It's for budjet economy.