Performance.getEntriesByName()

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The getEntriesByName() method returns a list of PerformanceEntry objects for the given name and type. The list's members (entries) can be created by making performance marks or measures (for example by calling the mark() method) at explicit points in time.

This method is exposed to Window and Worker interfaces.

Syntax

entries = window.performance.getEntriesByName(name, type);

Arguments

name
The name of the entry to retrieve.
type Optional
The type of entry to retrieve such as "mark". The valid entry types are listed in PerformanceEntry.entryType.

Return value

entries
A list of PerformanceEntry objects that have the specified name and type. If the type argument is not specified, only the name will be used to determine the entries to return. The items will be in chronological order based on the entries' startTime. If no objects meet the specified criteria, an empty list is returned.

Example

function use_PerformanceEntry_methods() {
  log("PerformanceEntry tests ...");

  if (performance.mark === undefined) {
    log("... performance.mark Not supported");
    return;
  }

  // Create some performance entries via the mark() method
  performance.mark("Begin");
  do_work(50000);
  performance.mark("End");
  performance.mark("Begin");
  do_work(100000);
  performance.mark("End");
  do_work(200000);
  performance.mark("End");

  // Use getEntries() to iterate through the each entry
  var p = performance.getEntries();
  for (var i=0; i < p.length; i++) {
    log("Entry[" + i + "]");
    check_PerformanceEntry(p[i]);
  }

  // Use getEntries(name, entryType) to get specific entries
  p = performance.getEntries({name : "Begin", entryType: "mark"});
  for (var i=0; i < p.length; i++) {
    log("Begin[" + i + "]");
    check_PerformanceEntry(p[i]);
  }

  // Use getEntriesByType() to get all "mark" entries
  p = performance.getEntriesByType("mark");
  for (var i=0; i < p.length; i++) {
    log ("Mark only entry[" + i + "]: name = " + p[i].name + 
         "; startTime = " + p[i].startTime + 
         "; duration  = " + p[i].duration);
  }

  // Use getEntriesByName() to get all "mark" entries named "Begin"
  p = performance.getEntriesByName("Begin", "mark");
  for (var i=0; i < p.length; i++) {
    log ("Mark and Begin entry[" + i + "]: name = " + p[i].name + 
         "; startTime = " + p[i].startTime + 
         "; duration  = " + p[i].duration);
  }
}

Specifications

Specification Status Comment
Performance Timeline Time Level 2
The definition of 'getEntriesByName()' in that specification.
Editor's Draft  
Performance Timeline
The definition of 'getEntriesByName()' in that specification.
Recommendation Initial definition.

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support. (Yes) (Yes) (Yes) No support No support
Feature Android Firefox Mobile (Gecko) Firefox OS IE Phone Opera Mobile Safari Mobile
Basic support. (Yes) 25.0 (25.0) 1.2 (25.0) 10.0 No support No support

Document Tags and Contributors

 Contributors to this page: rolfedh, AFBarstow
 Last updated by: rolfedh,