tenfourfox/dom/webidl/HeapSnapshot.webidl
Cameron Kaiser c9b2922b70 hello FPR
2017-04-19 00:56:45 -07:00

68 lines
2.3 KiB
Plaintext

/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/.
*/
/**
* A HeapSnapshot represents a snapshot of the heap graph
*/
[ChromeOnly, Exposed=(Window,System,Worker)]
interface HeapSnapshot {
/**
* A time stamp of when the heap snapshot was taken, if available. Units are
* microseconds since midnight (00:00:00) 1 January 1970 UTC.
*/
readonly attribute unsigned long long? creationTime;
/**
* Take a census of the heap snapshot.
*
* This is the same as |Debugger.Memory.prototype.takeCensus|, but operates on
* the offline heap snapshot's serialized heap graph rather than the live heap
* graph. The same optional configuration options that can be passed to that
* function can be passed here.
*
* The returned value is determined by the `"breakdown"` option used, and is
* usually a `Map`, `Object`, or `Array`. For example, the following breakdown
*
* {
* by: "coarseType",
* objects: { by: "objectClass" },
* other: { by: "internalType" }
* }
*
* produces a result like this:
*
* {
* "objects": {
* "Function": { "count": 404, "bytes": 37328 },
* "Object": { "count": 11, "bytes": 1264 },
* "Debugger": { "count": 1, "bytes": 416 },
* "ScriptSource": { "count": 1, "bytes": 64 },
* // ... omitted for brevity...
* },
* "scripts": { "count": 1, "bytes": 0 },
* "strings": { "count": 701, "bytes": 49080 },
* "other": {
* "js::Shape": { "count": 450, "bytes": 0 },
* "js::BaseShape": { "count": 21, "bytes": 0 },
* "js::ObjectGroup": { "count": 17, "bytes": 0 }
* }
* }
*
* See the `takeCensus` section of the `js/src/doc/Debugger/Debugger.Memory.md`
* file for detailed documentation.
*/
[Throws]
any takeCensus(object? options);
/**
* Compute the dominator tree for this heap snapshot.
*
* @see DominatorTree.webidl
*/
[Throws]
DominatorTree computeDominatorTree();
};