At the moment we're trying to decide whether to move our datacenter from the west coast (Corvallis, OR) to the east coast (NY, NY).
However, I am seeing some disturbing latency numbers from my location (Berkeley, CA) to the NYC host. Here's a sample result, retrieving a small .png logo file in Google Chrome and using the dev tools to see how long the request takes:
Berkeley to NYC server:
215 ms latency, 46ms transfer time, 261ms total
Berkeley to Corvallis server:
114ms latency, 41ms transfer time, 155ms total
some URLs if you want to try yourself:
http://careers.stackoverflow.com/content/cso/img/logo.png (NY, NY)
http://serverfault.com/cache/logo.png (Corvallis, OR)
It makes sense that Corvallis, OR is geographically closer to Berkeley, CA so I expect the connection to be a bit faster.. but I'm seeing an increase in latency of +100ms when I perform the same test to the NYC server. That seems .. excessive to me. Particularly since the time spent transferring the actual data only went up 10%, yet the latency went up ten times as much!
That feels... wrong... to me.
I found a few links here that were helpful (through Google no less!) ...
http://serverfault.com/questions/63531/does-routing-distance-affect-performance-significantly
http://serverfault.com/questions/61719/how-does-geography-affect-network-latency
http://serverfault.com/questions/6210/latency-in-internet-connections-from-europe-to-usa
... but nothing authoritative.
So, is this normal? It doesn't feel normal. What is the "typical" latency I should expect when moving network packets from the east coast <--> west coast of the USA?