W3C

- DRAFT -

Web Performance

21 Oct 2015

Agenda

See also: IRC log

Attendees

Present
Yoav, Ilya, plh
Regrets
Todd
Chair
Ilya
Scribe
plh

Contents


Clarify {transfer,encodedBody,decodedBody}size

- https://github.com/w3c/resource-timing/pull/41

Ilya: based on implementation feedback: clarifying what those values should report when you don't hit the network
... need to address the feedback from Yoav

<igrigorik> Pull: https://github.com/w3c/resource-timing/pull/41

Ilya: we can reuse the concepts from fetch
... I'll make it clearer
... distinguishing between not allowed
... if we don't pass the timing check algo, we report 0

Yoav: it might be a breaking change
... what if the resource was actually 0?
... the distinction with not allowed could be meaningful

Ilya: that's the behavior we have for other attributes (we report time 0)
... if you hit the network, you'll never get non-0 for transferSize
... you can only know the transferSize if we pass the TAO header
... if we don't, we always report 0
... so if we report not allowed, then we may be saying too much

Yoav: I wonder what this would expose... TAO aren't user specific
... the privacy concern would be if the server sends TAO headers depending on the user being logged in or not
... not sure if TAO is used that way

Ilya: for consistency, if TAO disallows timing values, we report 0

Yoav: I agree but we should try to change this

Ilya: if we make nullable or undefined, we could break pages
... we should look into this in a different issue

Yoav: I'll open one

Ilya: I'll keep it as 0 for now

<scribe> ACTION: Yoav to open an issue on RT regarding TAO information and attributes [recorded in http://www.w3.org/2015/10/21-webperf-minutes.html#action01]

<trackbot> Created ACTION-161 - Open an issue on rt regarding tao information and attributes [on Yoav Weiss - due 2015-10-28].

Ilya: with the current, if any of the requests failed during redirects, we set the attributes to 0.

Yoav: if the conditions don't match and we're not adding the http overhead.... I guess that's ok.

<scribe> ACTION: Ilya to update pull 41 with network fetches [recorded in http://www.w3.org/2015/10/21-webperf-minutes.html#action02]

<trackbot> Created ACTION-162 - Update pull 41 with network fetches [on Ilya Grigorik - due 2015-10-28].

<igrigorik> FF bug: https://bugzilla.mozilla.org/show_bug.cgi?id=1154309

Ilya: firefox is implementing right now. hoping Q4 for chrome but no one is committed to it.

Page Visibility

<igrigorik> https://github.com/w3c/page-visibility/pull/16

Ilya: I was set to remove unloaded, but I found some issues
... we define both visible and the visibilityState with different algorithms
... so we should fix that
... I'm proposing we drop the setting but run the algorithm instead

Yoav: I'm guessing the implementation will set the variable instead of running the algo
... as long as we're identical in terms of functionality, we should be fine

Ilya: prerender is mandatory instead of optional
... everyone implements it
... Safari is very aggressive in using prerender
... if you paste in the address bar, it will trigger prerendering based on predictions

yoav: as long as clearing the cache will also clear predictions, you should be fine

Ilya: next step is to keep circulating the PR
... one outstanding change as well

plh: user interaction task source?

Ilya: wasn't sure about that one. will try to get Anne or Boris to look at it

Yoav: we need to separate issue for unloaded deprecation/removal

ILya: ok

<scribe> ACTION: Ilya to open bug for unloaded in PV [recorded in http://www.w3.org/2015/10/21-webperf-minutes.html#action03]

<trackbot> Created ACTION-163 - Open bug for unloaded in pv [on Ilya Grigorik - due 2015-10-28].

<scribe> ACTION: Ilya: to add triggers for changing the value of visibility state [recorded in http://www.w3.org/2015/10/21-webperf-minutes.html#action04]

<trackbot> Created ACTION-164 - Add triggers for changing the value of visibility state [on Ilya Grigorik - due 2015-10-28].

<scribe> ACTION: Ilya to check the task source in PV [recorded in http://www.w3.org/2015/10/21-webperf-minutes.html#action05]

<trackbot> Created ACTION-165 - Check the task source in pv [on Ilya Grigorik - due 2015-10-28].

Ilya: then we'll have to update resource hints

"Red warning" for TR/hr-time

Yoav: +1 to renaming idea

<igrigorik> +1, let's discuss this more at TPAC as well

Drop prerenderSwitch from nav timing 2

Ilya: nobody implements prerenderSwitch
... and it makes it tricky to understand when it is set
... so not clear if it is necessary

clearMarks

Ilya: with performance observers, the buffer logic is expressed with simple JS

<igrigorik> https://github.com/w3c/user-timing/pull/13#issuecomment-149985067

TPAC

<igrigorik> https://docs.google.com/document/d/1IPM75UYlPPIPnr5uZMPYwb9EcOvquyWTo1uGqHeNafI/edit

Summary of Action Items

[NEW] ACTION: Ilya to check the task source in PV [recorded in http://www.w3.org/2015/10/21-webperf-minutes.html#action05]
[NEW] ACTION: Ilya to open bug for unloaded in PV [recorded in http://www.w3.org/2015/10/21-webperf-minutes.html#action03]
[NEW] ACTION: Ilya to update pull 41 with network fetches [recorded in http://www.w3.org/2015/10/21-webperf-minutes.html#action02]
[NEW] ACTION: Ilya: to add triggers for changing the value of visibility state [recorded in http://www.w3.org/2015/10/21-webperf-minutes.html#action04]
[NEW] ACTION: Yoav to open an issue on RT regarding TAO information and attributes [recorded in http://www.w3.org/2015/10/21-webperf-minutes.html#action01]
 
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Minutes formatted by David Booth's scribe.perl version 1.140 (CVS log)
$Date: 2015/10/21 20:33:42 $

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This is scribe.perl Revision: 1.140  of Date: 2014-11-06 18:16:30  
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Guessing input format: RRSAgent_Text_Format (score 1.00)

No ScribeNick specified.  Guessing ScribeNick: plh
Inferring Scribes: plh
Present: Yoav Ilya plh
Regrets: Todd
Agenda: https://lists.w3.org/Archives/Public/public-web-perf/2015Oct/0007.html
Got date from IRC log name: 21 Oct 2015
Guessing minutes URL: http://www.w3.org/2015/10/21-webperf-minutes.html
People with action items: ilya yoav

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