[viraptor]

I still think you need to specify what latency are we talking about. Scheduling latency is about scheduling. Network interface latency is about putting data in the buffer and then on the wire. Network latency is about actually delivering the packet. Web page latency is about time-to-render. First few pages of google results about various types of latency always qualify it with some other word, so it's not clear anymore what people mean if they just say "latency".

These are all both durations in one context and latencies in another. For the app syscalls are "how long did I have to wait for that call to give me a result" so a latency and a duration as well. (just because it's a period of time)

[TickleSteve]

Regarding Web Page latency.... I would expect web developers to be more slack on these types of definitions as they are so far removed from the hardware. Still, having said that: http://blog.iweb.com/en/2014/02/understanding-analyzing-redu...

This indicates that 'web page' latency is nothing to do with redraw-duration, but more akin to network-latency, but for the page as a whole. In comparison to redraw-duration (which is entirely client-side, web-page latency is the time to transit the network... i.e. latency.

In all the above cases, 'latency' is the delay between the stimulus and response, not the processing time.

I'll leave you with the top Google result for 'latency':

"Latency is a time interval between the stimulation and response, or, from a more general point of view, as a time delay between the cause and the effect of some physical change in the system being observed."