1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 'use strict'; 6 7 /** 8 * @fileoverview Model is a parsed representation of the 9 * TraceEvents obtained from base/trace_event in which the begin-end 10 * tokens are converted into a hierarchy of processes, threads, 11 * subrows, and slices. 12 * 13 * The building block of the model is a slice. A slice is roughly 14 * equivalent to function call executing on a specific thread. As a 15 * result, slices may have one or more subslices. 16 * 17 * A thread contains one or more subrows of slices. Row 0 corresponds to 18 * the "root" slices, e.g. the topmost slices. Row 1 contains slices that 19 * are nested 1 deep in the stack, and so on. We use these subrows to draw 20 * nesting tasks. 21 * 22 */ 23 'use strict'; 24 base.exportTo('tracing', function() { 25 26 var nextGUID = 1; 27 var GUID = { 28 allocate: function() { 29 return nextGUID++; 30 } 31 }; 32 33 return { 34 GUID: GUID 35 }; 36 37 }); 38
