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-rw-r--r--dom/heapsnapshot/HeapAnalysesWorker.js303
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diff --git a/dom/heapsnapshot/HeapAnalysesWorker.js b/dom/heapsnapshot/HeapAnalysesWorker.js
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+/* 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/. */
+/* global ThreadSafeChromeUtils*/
+
+// This is a worker which reads offline heap snapshots into memory and performs
+// heavyweight analyses on them without blocking the main thread. A
+// HeapAnalysesWorker is owned and communicated with by a HeapAnalysesClient
+// instance. See HeapAnalysesClient.js.
+
+"use strict";
+
+importScripts("resource://gre/modules/workers/require.js");
+importScripts("resource://devtools/shared/worker/helper.js");
+const { censusReportToCensusTreeNode } = require("resource://devtools/shared/heapsnapshot/census-tree-node.js");
+const DominatorTreeNode = require("resource://devtools/shared/heapsnapshot/DominatorTreeNode.js");
+const CensusUtils = require("resource://devtools/shared/heapsnapshot/CensusUtils.js");
+
+const DEFAULT_START_INDEX = 0;
+const DEFAULT_MAX_COUNT = 50;
+
+/**
+ * The set of HeapSnapshot instances this worker has read into memory. Keyed by
+ * snapshot file path.
+ */
+const snapshots = Object.create(null);
+
+/**
+ * The set of `DominatorTree`s that have been computed, mapped by their id (aka
+ * the index into this array).
+ *
+ * @see /dom/webidl/DominatorTree.webidl
+ */
+const dominatorTrees = [];
+
+/**
+ * The i^th HeapSnapshot in this array is the snapshot used to generate the i^th
+ * dominator tree in `dominatorTrees` above. This lets us map from a dominator
+ * tree id to the snapshot it came from.
+ */
+const dominatorTreeSnapshots = [];
+
+/**
+ * @see HeapAnalysesClient.prototype.readHeapSnapshot
+ */
+workerHelper.createTask(self, "readHeapSnapshot", ({ snapshotFilePath }) => {
+ snapshots[snapshotFilePath] =
+ ThreadSafeChromeUtils.readHeapSnapshot(snapshotFilePath);
+ return true;
+});
+
+/**
+ * @see HeapAnalysesClient.prototype.deleteHeapSnapshot
+ */
+workerHelper.createTask(self, "deleteHeapSnapshot", ({ snapshotFilePath }) => {
+ let snapshot = snapshots[snapshotFilePath];
+ if (!snapshot) {
+ throw new Error(`No known heap snapshot for '${snapshotFilePath}'`);
+ }
+
+ snapshots[snapshotFilePath] = undefined;
+
+ let dominatorTreeId = dominatorTreeSnapshots.indexOf(snapshot);
+ if (dominatorTreeId != -1) {
+ dominatorTreeSnapshots[dominatorTreeId] = undefined;
+ dominatorTrees[dominatorTreeId] = undefined;
+ }
+});
+
+/**
+ * @see HeapAnalysesClient.prototype.takeCensus
+ */
+workerHelper.createTask(self, "takeCensus", ({ snapshotFilePath, censusOptions, requestOptions }) => {
+ if (!snapshots[snapshotFilePath]) {
+ throw new Error(`No known heap snapshot for '${snapshotFilePath}'`);
+ }
+
+ let report = snapshots[snapshotFilePath].takeCensus(censusOptions);
+ let parentMap;
+
+ if (requestOptions.asTreeNode || requestOptions.asInvertedTreeNode) {
+ const opts = { filter: requestOptions.filter || null };
+ if (requestOptions.asInvertedTreeNode) {
+ opts.invert = true;
+ }
+ report = censusReportToCensusTreeNode(censusOptions.breakdown, report, opts);
+ parentMap = CensusUtils.createParentMap(report);
+ }
+
+ return { report, parentMap };
+});
+
+/**
+ * @see HeapAnalysesClient.prototype.getCensusIndividuals
+ */
+workerHelper.createTask(self, "getCensusIndividuals", request => {
+ const {
+ dominatorTreeId,
+ indices,
+ censusBreakdown,
+ labelBreakdown,
+ maxRetainingPaths,
+ maxIndividuals,
+ } = request;
+
+ const dominatorTree = dominatorTrees[dominatorTreeId];
+ if (!dominatorTree) {
+ throw new Error(
+ `There does not exist a DominatorTree with the id ${dominatorTreeId}`);
+ }
+
+ const snapshot = dominatorTreeSnapshots[dominatorTreeId];
+ const nodeIds = CensusUtils.getCensusIndividuals(indices, censusBreakdown, snapshot);
+
+ const nodes = nodeIds
+ .sort((a, b) => dominatorTree.getRetainedSize(b) - dominatorTree.getRetainedSize(a))
+ .slice(0, maxIndividuals)
+ .map(id => {
+ const { label, shallowSize } =
+ DominatorTreeNode.getLabelAndShallowSize(id, snapshot, labelBreakdown);
+ const retainedSize = dominatorTree.getRetainedSize(id);
+ const node = new DominatorTreeNode(id, label, shallowSize, retainedSize);
+ node.moreChildrenAvailable = false;
+ return node;
+ });
+
+ DominatorTreeNode.attachShortestPaths(snapshot,
+ labelBreakdown,
+ dominatorTree.root,
+ nodes,
+ maxRetainingPaths);
+
+ return { nodes };
+});
+
+/**
+ * @see HeapAnalysesClient.prototype.takeCensusDiff
+ */
+workerHelper.createTask(self, "takeCensusDiff", request => {
+ const {
+ firstSnapshotFilePath,
+ secondSnapshotFilePath,
+ censusOptions,
+ requestOptions
+ } = request;
+
+ if (!snapshots[firstSnapshotFilePath]) {
+ throw new Error(`No known heap snapshot for '${firstSnapshotFilePath}'`);
+ }
+
+ if (!snapshots[secondSnapshotFilePath]) {
+ throw new Error(`No known heap snapshot for '${secondSnapshotFilePath}'`);
+ }
+
+ const first = snapshots[firstSnapshotFilePath].takeCensus(censusOptions);
+ const second = snapshots[secondSnapshotFilePath].takeCensus(censusOptions);
+ let delta = CensusUtils.diff(censusOptions.breakdown, first, second);
+ let parentMap;
+
+ if (requestOptions.asTreeNode || requestOptions.asInvertedTreeNode) {
+ const opts = { filter: requestOptions.filter || null };
+ if (requestOptions.asInvertedTreeNode) {
+ opts.invert = true;
+ }
+ delta = censusReportToCensusTreeNode(censusOptions.breakdown, delta, opts);
+ parentMap = CensusUtils.createParentMap(delta);
+ }
+
+ return { delta, parentMap };
+});
+
+/**
+ * @see HeapAnalysesClient.prototype.getCreationTime
+ */
+workerHelper.createTask(self, "getCreationTime", snapshotFilePath => {
+ if (!snapshots[snapshotFilePath]) {
+ throw new Error(`No known heap snapshot for '${snapshotFilePath}'`);
+ }
+ return snapshots[snapshotFilePath].creationTime;
+});
+
+/**
+ * @see HeapAnalysesClient.prototype.computeDominatorTree
+ */
+workerHelper.createTask(self, "computeDominatorTree", snapshotFilePath => {
+ const snapshot = snapshots[snapshotFilePath];
+ if (!snapshot) {
+ throw new Error(`No known heap snapshot for '${snapshotFilePath}'`);
+ }
+
+ const id = dominatorTrees.length;
+ dominatorTrees.push(snapshot.computeDominatorTree());
+ dominatorTreeSnapshots.push(snapshot);
+ return id;
+});
+
+/**
+ * @see HeapAnalysesClient.prototype.getDominatorTree
+ */
+workerHelper.createTask(self, "getDominatorTree", request => {
+ const {
+ dominatorTreeId,
+ breakdown,
+ maxDepth,
+ maxSiblings,
+ maxRetainingPaths,
+ } = request;
+
+ if (!(0 <= dominatorTreeId && dominatorTreeId < dominatorTrees.length)) {
+ throw new Error(
+ `There does not exist a DominatorTree with the id ${dominatorTreeId}`);
+ }
+
+ const dominatorTree = dominatorTrees[dominatorTreeId];
+ const snapshot = dominatorTreeSnapshots[dominatorTreeId];
+
+ const tree = DominatorTreeNode.partialTraversal(dominatorTree,
+ snapshot,
+ breakdown,
+ maxDepth,
+ maxSiblings);
+
+ const nodes = [];
+ (function getNodes(node) {
+ nodes.push(node);
+ if (node.children) {
+ for (let i = 0, length = node.children.length; i < length; i++) {
+ getNodes(node.children[i]);
+ }
+ }
+ }(tree));
+
+ DominatorTreeNode.attachShortestPaths(snapshot,
+ breakdown,
+ dominatorTree.root,
+ nodes,
+ maxRetainingPaths);
+
+ return tree;
+});
+
+/**
+ * @see HeapAnalysesClient.prototype.getImmediatelyDominated
+ */
+workerHelper.createTask(self, "getImmediatelyDominated", request => {
+ const {
+ dominatorTreeId,
+ nodeId,
+ breakdown,
+ startIndex,
+ maxCount,
+ maxRetainingPaths,
+ } = request;
+
+ if (!(0 <= dominatorTreeId && dominatorTreeId < dominatorTrees.length)) {
+ throw new Error(
+ `There does not exist a DominatorTree with the id ${dominatorTreeId}`);
+ }
+
+ const dominatorTree = dominatorTrees[dominatorTreeId];
+ const snapshot = dominatorTreeSnapshots[dominatorTreeId];
+
+ const childIds = dominatorTree.getImmediatelyDominated(nodeId);
+ if (!childIds) {
+ throw new Error(`${nodeId} is not a node id in the dominator tree`);
+ }
+
+ const start = startIndex || DEFAULT_START_INDEX;
+ const count = maxCount || DEFAULT_MAX_COUNT;
+ const end = start + count;
+
+ const nodes = childIds
+ .slice(start, end)
+ .map(id => {
+ const { label, shallowSize } =
+ DominatorTreeNode.getLabelAndShallowSize(id, snapshot, breakdown);
+ const retainedSize = dominatorTree.getRetainedSize(id);
+ const node = new DominatorTreeNode(id, label, shallowSize, retainedSize);
+ node.parentId = nodeId;
+ // DominatorTree.getImmediatelyDominated will always return non-null here
+ // because we got the id directly from the dominator tree.
+ node.moreChildrenAvailable = dominatorTree.getImmediatelyDominated(id).length > 0;
+ return node;
+ });
+
+ const path = [];
+ let id = nodeId;
+ do {
+ path.push(id);
+ id = dominatorTree.getImmediateDominator(id);
+ } while (id !== null);
+ path.reverse();
+
+ const moreChildrenAvailable = childIds.length > end;
+
+ DominatorTreeNode.attachShortestPaths(snapshot,
+ breakdown,
+ dominatorTree.root,
+ nodes,
+ maxRetainingPaths);
+
+ return { nodes, moreChildrenAvailable, path };
+});