Bandwidth doesn't matter: why network delay will always limit web performance and what to do about it
[presentation]Localização:12:30 - 13:20Abstract:
Many people think more bandwidth is the answer to the question of how to speed up website load time, but due to the request-response nature of the HTTP protocol, page-load time will always be a minimum of the number of items multiplied by the network delay between client and server. Even infinite bandwidth will not make things faster than the fundamental limit dictated by network delay.
This talk will highlight some of the problems with the current HTTP protocol, like its sensitivity to network delay and how that has affected both web development and browser/client evolution, making people create lots of imaginative workarounds for a protocol that was designed in another era, when web sites and pages were small and simple.
We will show exactly how network delay affects performance for the "chatty" protocol that is HTTP, how browsers try to counter the negative effects by parallelizing downloads, and how that in turn causes problems on the server side and sometimes in the network.
This presentation will explain the relationship between page load times and network delay, why bandwidth often doesn't matter, and discuss how modern browsers use parallel TCP connections in order to get around the network delay problem and speed up page load time.
We will also discuss what happens in the future, especially with the introduction of HTTP2, which will totally change the rules, and explore this new version from a performance perspective.