Bytes - conversion from string

In principle, this stack is quite fast. But you most likely just have heavily unoptimized code and/or SQL queries, no caching being used, etc. I deployed on approximately your configuration using the Apache + mod_wsgi + Nginx (for static files) stack, and such capacity was sufficient for that load. Look into MySQL query caching settings. Configuration parameters like (quote):

> query_cache_size — the size of the query cache. > query_cache_limit — the maximum size of a result set stored in the cache;  > query_cache_min_res_unit — the minimum size of a block stored in the cache;