HighLoad.RU is the conference focused on Building High Performance Systems and has speakers from most of top Russian Internet companies.
It is taking place in Moscow, Russia 24-25 of September and you should know a bit of Russian to attend 🙂
The conference has some international flavor though there are few people coming from other countries and giving talks in English. I too will fly from London but I’ll specially prepare Russian presentation versions.
Here is the full conference program.