I've got high execution time of HTTP request (ex. 42KB in 13s).
I'm using haproxy to load balance traffic. Static files are server by lighttpd behind varnish accelerator. So... it should be served below the speed of light :P
Long DNS Lookup: pic1
Long receive: pic2
Simulationous download: pic3
I use GoogleDNS. The servers are in the USA. Firstly I added IPs to /etc/hosts to ommit DNS query. Secondly I migrated static to separate machine omiting haproxy. In that's way it is connecting direct to varnish. The traffic is not big, because it's only development, but it happens also in production.
After changes: pic4
It's a bit better, but it's still sloooooow...