- From: Stefan Håkansson LK <stefan.lk.hakansson@ericsson.com>
- Date: Wed, 21 Dec 2016 13:57:26 +0000
- To: Todd Reifsteck <toddreif@microsoft.com>, Ilya Grigorik <igrigorik@google.com>
- CC: "public-web-perf@w3.org" <public-web-perf@w3.org>
Hi Todd, thanks for your input. I filed two issues to help us keep track: https://github.com/w3c/webrtc-stats/issues/121 https://github.com/w3c/webrtc-stats/issues/120 Br, Stefan On 21/12/16 00:11, Todd Reifsteck wrote: > 2 additional questions: > > * It does not appear that this specification clearly defines when the > various Stat objects are created and what is responsible for > emitting the various Stat objects. Is another specification > responsible for that? > o It would be useful to link to that as it seems critical to > ensuring cross-browser compat. > * Some pieces of the text hint that a Stat object’s members can be > changed after it is returned. But an example shows 2 objects being > compared to see how a baseline compares to a later “report”. Can > stat object’s values be changed after they are returned? > o http://www.w3.org/TR/2016/WD-webrtc-stats-20161214/#lifetime-of-stats-objects > hints that an object that has been returned to JavaScript may > change between accesses, but I could be misreading it. > > > > -Todd > > > > *From:* Ilya Grigorik [mailto:igrigorik@google.com] > *Sent:* Tuesday, December 20, 2016 11:52 AM > *To:* Stefan Håkansson LK <stefan.lk.hakansson@ericsson.com> > *Cc:* public-web-perf@w3.org; Todd Reifsteck <toddreif@microsoft.com> > *Subject:* Re: Review of WebRTC Statistics from Web Performance Working > Group > > > > Hi Stefan. > > > > On Wed, Dec 14, 2016 at 1:29 AM, Stefan Håkansson LK > <stefan.lk.hakansson@ericsson.com > <mailto:stefan.lk.hakansson@ericsson.com>> wrote: > > Dear Web Performance Working Group, > > The WebRTC Working Group is working toward publishing its WebRTC > Statistics API to Candidate Recommendation and is thus seeking review > from a variety of groups on the document: > > https://www.w3.org/TR/2016/WD-webrtc-stats-20161214/ > > We are particularly interested on feedback from the Web Performance > Working Group on possible alignments needed between the names, value > spaces and design of the statistics exposed in our documents with the > ones the Web Performance Working Group has brought through its > various APIs. > > > > On a quick scan, I didn't spot any substantive problems. That said, a > few nitpicks and thoughts: > > * Provide a normative reference [1] for DOMHighResTimeStamp? Want to > make sure that time origin definitions are aligned across > implementations. > * Stats are associated with each stream, which means that application > developers have to manually instrument each stream. Is there a use > case for analytics / third-party instrumentation to gather similar > stats? E.g. it would be nice if existing RUM providers could > auto-gather stats without monkey-patching all the WebRTC APIs to > figure out when new streams are initiated, etc. > > o Performance Timeline provides PerformanceObserver [2] interface > which allows anyone to register and listen for events. It might > be worth considering, if it makes sense, emitting some WebRTC > related events via this mechanism... which could stream specific > or aggregated. > > I'd be curious to hear from RUM vendors/folks if and how they currently > instrument WebRTC. > > > > Cheers. > > ig > > > > [1] https://www.w3.org/TR/hr-time-2/#dom-domhighrestimestamp > > [2] https://www.w3.org/TR/performance-timeline-2/#the-performanceobserver-interface >
Received on Wednesday, 21 December 2016 13:59:45 UTC