Incorrect behavior populating ResourceTimings performance buffer

Confirmed Issue #16739941 • Assigned to Venkat K.


Fred s.
Apr 4, 2018
This issue is public.
Found in
  • Microsoft Edge
  • Internet Explorer
Standard affected
Resource Timing Level 2

Reported by 1 person

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Steps to reproduce

IE 11 and Edge will create an partial entry in the ResourceTimings performance entry buffer array, initially comprised of the below data. As the XHR goes through its lifecycle, the additional timings are updated. This behavior runs contrary to the Resource Timings spec where the processing model requires that the ResourceTiming event be complete before adding to the buffer (see step 21 via this link

The scenario is easy to reproduce simply by creating a long running xhr call and observing the resource timing buffer while the xhr is running.

Also, see conversation here:

{ "name":"", "entryType":"resource", "startTime":995.896, "duration":0, "initiatorType":"xmlhttprequest", "redirectStart":0, "redirectEnd":0, "fetchStart":0, "domainLookupStart":0, "domainLookupEnd":0, "connectStart":0, "connectEnd":0, "secureConnectionStart":0, "requestStart":0, "responseStart":0, "responseEnd":0 }


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Comments and activity

  • Microsoft Edge Team

    Changed Assigned To to “Steven K.”

    Changed Steps to Reproduce

  • Hi Fred,

    Thank you for submitting this issue.  Do you by chance have simplified repro for this issue?  I know it sounds like a basic test scenario, however, it saves us time and minimizes various repro issues as a general rule.


  • I am not seeing this behavior in 16299.371.  I.e. I do not see a resource record created until there is a responseEnd value that is non-zero.

    var resources = performance.getEntriesByType(“resource”);

    Will you provide the extended version of Windows 10 you are using when you see this behavior?  Win + S and type “winver” and hit enter.

  • I take that back.  I am able to reproduce this issue.  I did not set my interval timer small enough to catch the issue or as you mentioned create a fetch/xhr request that is long enough.

    I have attached my repro code in case you want to verify it.  The script prints out all performance records/entries every 100 ms and stops after 10 timeouts.


  • Microsoft Edge Team

    Changed Assigned To to “Arvind M.”

    Changed Assigned To to “Arvind M.”

  • Thanks Steve. Is there a planned fix date for this? Will this be fixed in IE11 or only Edge?

  • Microsoft Edge Team

    Changed Assigned To to “Venkat K.”

    Changed Status to “Confirmed”

  • Hi, any update on this issue? Is there a planned fix for this?

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