Re: =[xhr]

This is an intranet application.  The server is in the next room (locked, 
of course.)



From:   David Bruant <bruant.d@gmail.com>
To:     Austin William Wright <aaa@bzfx.net>, Glenn Maynard 
<glenn@zewt.org>, 
Cc:     nmork_consultant@cusa.canon.com, "Tab Atkins Jr." 
<jackalmage@gmail.com>, public-webapps <public-webapps@w3.org>
Date:   08/02/2014 03:41 AM
Subject:        Re: =[xhr]



Le 02/08/2014 11:11, Austin William Wright a écrit :
> Maybe there's another reason: Good idea or no, removing this feature 
> DOES break reverse compatibility with the de-facto behavior of many 
> Web browsers.
Everyone who wants sync xhr to disappear is well-aware. That's the 
reason it hasn't been removed yet.

Just as a reminder, we live on Planet Earth where the distance between 
two computers who want to communicate with one another can be 20.000km. 
A signal at speed light takes 60ms. But our network isn't either at 
speed light nor in straight line, so the delay is easily multiplied by 
20 and that's very optimistic. And that's just the latency. Bandwidth 
considerations and data processing times aren't free.
On the other hand, we're human beings and notice 100ms delays and all 
evidence converge in the direction of saying that human beings are 
frustrated when they feel a delay, so making people wait is terrible. 
(interesting talk which discusses perceived performance at one point 
http://vimeo.com/71278954 )
Sync xhr forces a delay and there is no way around that, ergo, it's 
terrible.

I'm probably not old enough to accurately make this comparison, but 
blocking I/O looks like it's 2010-era GOTO. I heard when higher-level 
programming came around, some people were strong defenser of GOTO. Now, 
most people have moved to higher-level constructs.
I think the same fate is waiting for blocking I/O.

David