Performance.getEntries()

The getEntries() method returns a list of PerformanceEntry objects for a given filter. 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

General syntax:

entries = window.performance.getEntries();
entries = window.performance.getEntries(PerformanceEntryFilterOptions);

Specific usage:

entries = performance.getEntries({name: "entry_name", entryType: "mark"});

Arguments

PerformanceEntryFilterOptions Optional

PerformanceEntryFilterOptions is a dictionary with the following fields:

• "name", the name of a performance entry.
• "entryType", the entry type. The valid entry types are listed in the PerformanceEntry.entryType method.
• "initiatorType", the type of the initiating resource (for example an HTML element). The values are defined by the PerformanceResourceTiming.initiatorType interface.

Return value

entries

A list of PerformanceEntry objects that meets the criteria of the filter. The items will be in chronological order based on the entries' startTime. If no objects that meet the filter are found, an empty list is returned. If no argument is given, all entries are 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

Browser compatibility