[minutes] 20100915 Web Performance

Available at

             Web Performance Working Group Teleconference

15 Sep 2010

   See also: [2]IRC log

      [2] http://www.w3.org/2010/09/15-webperf-irc


          Steve, Anderson, Tony, Arvind, Plh, Jason





     * [3]Topics
         1. [4]f2f meeting planning
     * [5]Summary of Action Items

October f2f meeting planning

   Arvind: End of week, meeting in mountain view, date 10/5/2010, from
   noon to 5pm.

   plh: may not be able to come for a subsequent 5hr meeting in Moutain

   Arvind: keep the 12-5 for the first f2f, get agenda set by next week
   ... if we have enough items on the agenda extend the meeting to all
   ... block out rooms at google for the entire day

   Anderson: sounds great

   Arvind: plh do you have advice to set the agenda?
   ... already have the basic agenda to discuss the three specs

   plh: we should discuss testing as well

   Arvind: place to add agenda?

   plh: can send agenda items to the mailing list

   Arvind: mailing list is sufficient, with a link to a document

   Anderson: comfortable with establishing the agenda over email, low

   Arvind: send an email to add to the list

TPAC f2f

   plh: got lucky we got room, monday and tuesday

   plh, nov 1st and nov 2nd, web apps working group will be meeting at
   the same time, one other thing, there is a fee to cover the costs.
   for each attendee register before oct 22nd

   plh: fee after 10/22 is dramatically increased, costs rise for late

   Arvind: potentially meet with the web apps working group at tpac
   ... ask them for a slot to present

   plh: everyone in the same room for a technical plannery day

   Arvind: send email to web app chairs

   <plh> see [6]http://www.w3.org/Member/Mail/ for contact information

      [6] http://www.w3.org/Member/Mail/

   Anderson: send feedback to the email list for agenda items and goals
   for meeting in tpac before committing to attending

   plh: one goal that can be satisfied with tpac is establishing test

   Arvind: let's establish the agenda through the email list for tpac
   and the f2f in mountain view
   ... let's get to item to 1 and 2
   ... let's start with the next set of items

processing Model, requestEnd and responseStart

   Anderson: analyzed phases with tools
   ... look at it from the wire or the browser

   Tony: some things are not present from the browser perspective, do
   we consider, browser phase or network stack
   ... maybe answer is both, sending phase, network view, request phase
   from the browser view
   ... the way the spec in webkit, reflects network view, the actual
   sending of data, as opposed to time to get back

   Anderson: the phases are broken down into browser work, sending
   request, waiting for server, first byte

   Steve: browsers may be downloading of resources before added to the
   dom, i can look at firebug netpanel and other tools and see when the
   request was sent over the wire
   ... do not lose this ability in the web timing spec, as a web
   developer i have no ability to measure how long it too on the
   network to download the jscript file
   ... lump together may lose this interesting data

   Nic: this conversation is intended to cover, the requestEnd phase in
   the IE implementation the point that we get the first byte back from
   the server, the webkit implementation is the browser has sent the
   request from the browser.
   ... approach taken was that from the user agent point of view, there
   is a consistent story across user agents.
   ... concern with perspective of sending the bytes to the server,
   some user agents sit on an abstraction of the network layer.
   ... in IE, sits on the abstraction of browser, wininet, tcp. the
   browser may not have insight into the lower layers.
   ... difference between the browser queuing the payload from when it
   actually was sent out.
   ... responseStart is not the time the server sends the response,
   it's the time the first byte was received in the browser. we are
   flexible for input.
   ... we want to make sure we can satisify the requirements as stated
   in the spec and is consistent in user agents.

   Steve: is there something in the spec that defines the requestEnd,
   when you're done with sending and receiving.

   Nic: definition in spec: time user agent finishes request the
   current document from the server.

   Tony: good time to have zhiheng on the call.
   ... get unique datapoint with different data point between
   requestEnd and responseStart, capture that the user agent spends
   time uploading.
   ... not arguing one or another, key point to note here, is it
   important to measure time spent uploading request. okay with the
   phase with get me this, i got something back from the server.

   Anderson: request phase can encapsulate a large upload. it captures
   a large upload and a long latency

   Tony: Chrome network stack is re-written for multiple platform
   ... usually from the browser perspective, there is no insight, if
   this is something to be difficult to implement, be interested to
   hear Mozilla's take. maybe it's nto worth breaking out sending and
   waiting for server., be interesting to hear mozilla's thoughts and
   zhiheng's thought.
   ... more parties need input here.

   Anderson: value input from other user agents on this matter.

   plh: can send emails to mozilla and apple if it helps?

   Anderson: absolutely

   Arvind: let's do that.

   <plh> ACTION: plh to reach out to Mozilla and Apple [recorded in

   <trackbot> Created ACTION-4 - Reach out to Mozilla and Apple [on
   Philippe Le H├ęgaret - due 2010-09-22].

the addition of requestCount and uniqueDomains

   Arvind: next item is addtion of requestCount and uniqueDomains

   Anderson: was introduced in the 3rd platform preview, we would like
   ... provided to give top level information about the navigation, to
   decribe dynamically generated pages, show total requests and show
   number of domain name lookups

   Tony: in absence of resource timing, may not be necessary and
   duplicate resource timing. resource timing is going to be a large
   topic, there's a lot of hard issues there.
   ... maybe it is useful to have something on the root document to
   expose these.

   Arvind: is there ambiguity how to compute requestCount and

   Tony: need a point where these are lock down, such as the point of
   loadEventEnd, or some point in the document, in the case of dynamic
   additions of resources to the document.
   ... Can you desribe how it works in IE?

   Nic: requestCount as we've talking about is the count of scripts,
   images, css, objects, and iframes/subdocs.
   ... in our implementation there is no end point, it continuously
   updates. the requestCount will continue to increment.
   ... similar to uniqueDomains, root document domain + unique domain,
   we increment domains.
   ... added from feedback from web properties. this helps site
   developers gives a characteristic of the page load.

   Tony: these don't peer into subframes.

   Nic: yes

   Tony: if i have a resource in a redirect, it's only one request. i
   do like them, they may be redudant to resource timing.

   Nic: good point.

   Arvind: decide to include them or not?

   Tony: present to Zhiheng, i have no problems adding them to webkit
   if they are in the spec.

   Arvind: cover that next week.
   ... last item for today start discussion on resource timing and user

start Resource Timing and User Timing discussions

   Anderson: want to cover the scenarios to cover in resource timing,
   i. access to resource timing, ii. access to resource timing from
   resources that have a different origin from the root document. With
   the constraint of not disclosing browser history to an attacker.

   Arvind: can you put this on the email list?

   Anderson: Yes.

   Arvind: no items left.

   Anderson: We've covered all topics.

   Arvind: let's adjourn.

Summary of Action Items

   [NEW] ACTION: plh to reach out to Mozilla and Apple [recorded in

   [End of minutes]

Received on Wednesday, 15 September 2010 16:51:54 UTC