Re: [rtcweb] Prioritization

Harald Alvestrand <harald@alvestrand.no> Fri, 25 April 2014 15:02 UTC

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Date: Fri, 25 Apr 2014 17:02:23 +0200
From: Harald Alvestrand <harald@alvestrand.no>
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Subject: Re: [rtcweb] Prioritization
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On 04/25/2014 03:53 PM, Simon Perreault wrote:
> Le 2014-04-25 09:21, Harald Alvestrand a écrit :
>>> Suggestion: leave it up to implementations to interpret priority levels
>>> however they want. Reword the current text so that it becomes an
>>> *example* of what an implementation might do.
>> The problem with doing that is that it leads to completely inconsistent
>> behaviour.
> Understood. But is that something we should care about? I mean, if it
> does not lead to application developers doing "if (chrome) ... else if
> (firefox) ..." then behaviour inconsistency is of no consequence. I
> can't imagine a situation where that would happen if we leave it open.

I can imagine that happening. Consider a scenario where complete 
starvation is considered a Really Bad Thing.

if (firefox) {
    // higher priority channels will completely starve out lower 
priority ones. Don't.
   priority = normal
} else if (chrome) {
    // lower priority channels will get some packets through. That's OK.
    priority = high
} else {
    // I have no idea what will happen, let's play it safe.
    priority = normal
}


>
> Simon