Add m-esr52 at 52.6.0

1 files changed, 239 insertions, 0 deletions

diff --git a/toolkit/components/perfmonitoring/AddonWatcher.jsm b/toolkit/components/perfmonitoring/AddonWatcher.jsm
new file mode 100644
index 000000000..58decba85
--- /dev/null
+++ b/toolkit/components/perfmonitoring/AddonWatcher.jsm
@@ -0,0 +1,239 @@
+// -*- indent-tabs-mode: nil; js-indent-level: 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/. */
+
+"use strict";
+
+this.EXPORTED_SYMBOLS = ["AddonWatcher"];
+
+const { classes: Cc, interfaces: Ci, utils: Cu } = Components;
+
+Cu.import("resource://gre/modules/XPCOMUtils.jsm");
+
+XPCOMUtils.defineLazyModuleGetter(this, "Preferences",
+                                  "resource://gre/modules/Preferences.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "Task",
+                                  "resource://gre/modules/Task.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "console",
+                                  "resource://gre/modules/Console.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "PerformanceWatcher",
+                                  "resource://gre/modules/PerformanceWatcher.jsm");
+XPCOMUtils.defineLazyServiceGetter(this, "Telemetry",
+                                  "@mozilla.org/base/telemetry;1",
+                                  Ci.nsITelemetry);
+XPCOMUtils.defineLazyModuleGetter(this, "Services",
+                                  "resource://gre/modules/Services.jsm");
+XPCOMUtils.defineLazyServiceGetter(this, "IdleService",
+                                   "@mozilla.org/widget/idleservice;1",
+                                   Ci.nsIIdleService);
+
+/**
+ * Don't notify observers of slow add-ons if at least `SUSPICIOUSLY_MANY_ADDONS`
+ * show up at the same time. We assume that this indicates that the system itself
+ * is busy, and that add-ons are not responsible.
+ */
+let SUSPICIOUSLY_MANY_ADDONS = 5;
+
+this.AddonWatcher = {
+  /**
+   * Watch this topic to be informed when a slow add-on is detected and should
+   * be reported to the user.
+   *
+   * If you need finer-grained control, use PerformanceWatcher.jsm.
+   */
+  TOPIC_SLOW_ADDON_DETECTED: "addon-watcher-detected-slow-addon",
+
+  init: function() {
+    this._initializedTimeStamp = Cu.now();
+
+    try {
+      this._ignoreList = new Set(JSON.parse(Preferences.get("browser.addon-watch.ignore", null)));
+    } catch (ex) {
+      // probably some malformed JSON, ignore and carry on
+      this._ignoreList = new Set();
+    }
+
+    this._warmupPeriod = Preferences.get("browser.addon-watch.warmup-ms", 60 * 1000 /* 1 minute */);
+    this._idleThreshold = Preferences.get("browser.addon-watch.deactivate-after-idle-ms", 3000);
+    this.paused = false;
+  },
+  uninit: function() {
+    this.paused = true;
+  },
+  _initializedTimeStamp: 0,
+
+  set paused(paused) {
+    if (paused) {
+      if (this._listener) {
+        PerformanceWatcher.removePerformanceListener({addonId: "*"}, this._listener);
+      }
+      this._listener = null;
+    } else {
+      this._listener = this._onSlowAddons.bind(this);
+      PerformanceWatcher.addPerformanceListener({addonId: "*"}, this._listener);
+    }
+  },
+  get paused() {
+    return !this._listener;
+  },
+  _listener: null,
+
+  /**
+   * Provide the following object for each addon:
+   *  {number} occurrences The total number of performance alerts recorded for this addon.
+   *  {number} occurrencesSinceLastNotification The number of performances alerts recorded
+   *     since we last notified the user.
+   *  {number} latestNotificationTimeStamp The timestamp of the latest user notification
+   *     that this add-on is slow.
+   */
+  _getAlerts: function(addonId) {
+    let alerts = this._alerts.get(addonId);
+    if (!alerts) {
+      alerts = {
+        occurrences: 0,
+        occurrencesSinceLastNotification: 0,
+        latestNotificationTimeStamp: 0,
+      };
+      this._alerts.set(addonId, alerts);
+    }
+    return alerts;
+  },
+  _alerts: new Map(),
+  _onSlowAddons: function(addons) {
+    try {
+      if (IdleService.idleTime >= this._idleThreshold) {
+        // The application is idle. Maybe the computer is sleeping, or maybe
+        // the user isn't in front of it. Regardless, the user doesn't care
+        // about things that slow down her browser while she's not using it.
+        return;
+      }
+
+      if (addons.length > SUSPICIOUSLY_MANY_ADDONS) {
+        // Heuristic: if we are notified of many slow addons at once, the issue
+        // is probably not with the add-ons themselves with the system. We may
+        // for instance be waking up from hibernation, or the system may be
+        // busy swapping.
+        return;
+      }
+
+      let now = Cu.now();
+      if (now - this._initializedTimeStamp < this._warmupPeriod) {
+        // Heuristic: do not report slowdowns during or just after startup.
+        return;
+      }
+
+      // Report immediately to Telemetry, regardless of whether we report to
+      // the user.
+      for (let {source: {addonId}, details} of addons) {
+        Telemetry.getKeyedHistogramById("PERF_MONITORING_SLOW_ADDON_JANK_US").
+          add(addonId, details.highestJank);
+        Telemetry.getKeyedHistogramById("PERF_MONITORING_SLOW_ADDON_CPOW_US").
+          add(addonId, details.highestCPOW);
+      }
+
+      // We expect that users don't care about real-time alerts unless their
+      // browser is going very, very slowly. Therefore, we use the following
+      // heuristic:
+      // - if jank is above freezeThreshold (e.g. 5 seconds), report immediately; otherwise
+      // - if jank is below jankThreshold (e.g. 128ms), disregard; otherwise
+      // - if the latest jank was more than prescriptionDelay (e.g. 5 minutes) ago, reset number of occurrences;
+      // - if we have had fewer than occurrencesBetweenAlerts janks (e.g. 3) since last alert, disregard; otherwise
+      // - if we have displayed an alert for this add-on less than delayBetweenAlerts ago (e.g. 6h), disregard; otherwise
+      // - also, don't report more than highestNumberOfAddonsToReport (e.g. 1) at once.
+      let freezeThreshold = Preferences.get("browser.addon-watch.freeze-threshold-micros", /* 5 seconds */ 5000000);
+      let jankThreshold = Preferences.get("browser.addon-watch.jank-threshold-micros", /* 256 ms == 8 frames*/ 256000);
+      let occurrencesBetweenAlerts = Preferences.get("browser.addon-watch.occurrences-between-alerts", 3);
+      let delayBetweenAlerts = Preferences.get("browser.addon-watch.delay-between-alerts-ms", 6 * 3600 * 1000 /* 6h */);
+      let delayBetweenFreezeAlerts = Preferences.get("browser.addon-watch.delay-between-freeze-alerts-ms", 2 * 60 * 1000 /* 2 min */);
+      let prescriptionDelay = Preferences.get("browser.addon-watch.prescription-delay", 5 * 60 * 1000 /* 5 minutes */);
+      let highestNumberOfAddonsToReport = Preferences.get("browser.addon-watch.max-simultaneous-reports", 1);
+
+      addons = addons.filter(x => x.details.highestJank >= jankThreshold).
+        sort((a, b) => a.details.highestJank - b.details.highestJank);
+
+      for (let {source: {addonId}, details} of addons) {
+        if (highestNumberOfAddonsToReport <= 0) {
+          return;
+        }
+        if (this._ignoreList.has(addonId)) {
+          // Add-on is ignored.
+          continue;
+        }
+
+        let alerts = this._getAlerts(addonId);
+        if (now - alerts.latestOccurrence >= prescriptionDelay) {
+          // While this add-on has already caused slownesss, this
+          // was a long time ago, let's forgive.
+          alerts.occurrencesSinceLastNotification = 0;
+        }
+
+        alerts.occurrencesSinceLastNotification++;
+        alerts.occurrences++;
+
+        if (details.highestJank < freezeThreshold) {
+          if (alerts.occurrencesSinceLastNotification <= occurrencesBetweenAlerts) {
+            // While the add-on has caused jank at least once, we are only
+            // interested in repeat offenders. Store the data for future use.
+            continue;
+          }
+          if (now - alerts.latestNotificationTimeStamp <= delayBetweenAlerts) {
+            // We have already displayed an alert for this add-on recently.
+            // Wait a little before displaying another one.
+            continue;
+          }
+        } else if (now - alerts.latestNotificationTimeStamp <= delayBetweenFreezeAlerts) {
+          // Even in case of freeze, we want to avoid needlessly spamming the user.
+          // We have already displayed an alert for this add-on recently.
+          // Wait a little before displaying another one.
+          continue;
+        }
+
+        // Ok, time to inform the user.
+        alerts.latestNotificationTimeStamp = now;
+        alerts.occurrencesSinceLastNotification = 0;
+        Services.obs.notifyObservers(null, this.TOPIC_SLOW_ADDON_DETECTED, addonId);
+
+        highestNumberOfAddonsToReport--;
+      }
+    } catch (ex) {
+      Cu.reportError("Error in AddonWatcher._onSlowAddons " + ex);
+      Cu.reportError(Task.Debugging.generateReadableStack(ex.stack));
+    }
+  },
+
+  ignoreAddonForSession: function(addonid) {
+    this._ignoreList.add(addonid);
+  },
+  ignoreAddonPermanently: function(addonid) {
+    this._ignoreList.add(addonid);
+    try {
+      let ignoreList = JSON.parse(Preferences.get("browser.addon-watch.ignore", "[]"))
+      if (!ignoreList.includes(addonid)) {
+        ignoreList.push(addonid);
+        Preferences.set("browser.addon-watch.ignore", JSON.stringify(ignoreList));
+      }
+    } catch (ex) {
+      Preferences.set("browser.addon-watch.ignore", JSON.stringify([addonid]));
+    }
+  },
+
+  /**
+   * The list of alerts for this session.
+   *
+   * @type {Map<String, Object>} A map associating addonId to
+   *  objects with fields
+   *  {number} occurrences The total number of performance alerts recorded for this addon.
+   *  {number} occurrencesSinceLastNotification The number of performances alerts recorded
+   *     since we last notified the user.
+   *  {number} latestNotificationTimeStamp The timestamp of the latest user notification
+   *     that this add-on is slow.
+   */
+  get alerts() {
+    let result = new Map();
+    for (let [k, v] of this._alerts) {
+      result.set(k, Cu.cloneInto(v, this));
+    }
+    return result;
+  },
+};