Bug 1353013 - Be less aggressive about preloading about:newtab. r?florian
Based on a patch that Dão Gottwald <dao+bmo@mozilla.com> wrote.
We used to preload about:newtab as soon as a tab had finished being opened,
which meant that the first opened tab was _never_ preloaded, and that we
risked janking the browser immediately after the user opened a new tab
(which is, arguably, the worst time to do it, since the user is probably
about to navigate that tab somewhere).
This patch makes it so that about:newtab is preloaded after:
1) 1 second of user inactivity, and
2) When we have at least 40ms of idle time to spend in an idle callback.
The 1s and 40ms thresholds were chosen arbitrarily, and we might tune them
over time.
MozReview-Commit-ID: J5xkPQvCdW6
--- a/browser/base/content/browser.js
+++ b/browser/base/content/browser.js
@@ -1759,16 +1759,21 @@ var gBrowserInit = {
try {
DownloadsCommon.initializeAllDataLinks();
Cu.import("resource:///modules/DownloadsTaskbar.jsm", {})
.DownloadsTaskbar.registerIndicator(window);
} catch (ex) {
Cu.reportError(ex);
}
}, {timeout: 10000});
+
+ scheduleIdleTask(() => {
+ // Prepare preloaded browser for the next new tab to open.
+ gBrowser.requestPreloadBrowser();
+ });
},
// Returns the URI(s) to load at startup.
get _uriToLoadPromise() {
delete this._uriToLoadPromise;
return this._uriToLoadPromise = new Promise(resolve => {
// window.arguments[0]: URI to load (string), or an nsIArray of
// nsISupportsStrings to load, or a xul:tab of
--- a/browser/base/content/tabbrowser.xml
+++ b/browser/base/content/tabbrowser.xml
@@ -2109,25 +2109,65 @@
// and the URL is "about:newtab". We do not support preloading for
// custom newtab URLs.
return Services.prefs.getBoolPref("browser.newtab.preload") &&
!aboutNewTabService.overridden;
]]>
</body>
</method>
+ <field name="_preloadBrowserMinUserIdleSeconds">1</field>
+ <field name="_preloadBrowserMinIdlePeriodMs">40</field>
+ <method name="requestPreloadBrowser">
+ <body><![CDATA[
+ // Do nothing if we have a preloaded browser already or we're about
+ // to create one or preloading is disabled.
+ if (this._preloadedBrowser ||
+ this._preloadBrowserIdleObserver ||
+ !this._isPreloadingEnabled()) {
+ return;
+ }
+
+ this._preloadBrowserIdleObserver = (aSubject, aTopic) => {
+ if (aTopic != "idle") {
+ return;
+ }
+
+ Services.idle.removeIdleObserver(this._preloadBrowserIdleObserver,
+ this._preloadBrowserMinUserIdleSeconds);
+ this._preloadBrowserIdleObserver = null;
+
+ let idleCallback = deadline => {
+ if (deadline.timeRemaining() < this._preloadBrowserMinIdlePeriodMs) {
+ window.requestIdleCallback(idleCallback);
+ } else {
+ this._createPreloadBrowser();
+ }
+ };
+ window.requestIdleCallback(idleCallback);
+ };
+ Services.idle.addIdleObserver(this._preloadBrowserIdleObserver, this._preloadBrowserMinUserIdleSeconds);
+ ]]></body>
+ </method>
+
<method name="_createPreloadBrowser">
<body>
<![CDATA[
// Do nothing if we have a preloaded browser already
// or preloading of newtab pages is disabled.
if (this._preloadedBrowser || !this._isPreloadingEnabled()) {
return;
}
+ if (this._preloadBrowserIdleObserver) {
+ Services.idle.removeIdleObserver(this._preloadBrowserIdleObserver,
+ this._preloadBrowserMinUserIdleSeconds);
+ this._preloadBrowserIdleObserver = null;
+ }
+
let remoteType =
E10SUtils.getRemoteTypeForURI(BROWSER_NEW_TAB_URL,
gMultiProcessBrowser);
let browser = this._createBrowser({isPreloadBrowser: true, remoteType});
this._preloadedBrowser = browser;
let notificationbox = this.getNotificationBox(browser);
this.mPanelContainer.appendChild(notificationbox);
@@ -5944,16 +5984,22 @@
window.messageManager.removeMessageListener("contextmenu", this);
if (this._switcher) {
this._switcher.destroy();
}
}
Services.prefs.removeObserver("accessibility.typeaheadfind", this);
+
+ if (this._preloadBrowserIdleObserver) {
+ Services.idle.removeIdleObserver(this._preloadBrowserIdleObserver,
+ this._preloadBrowserMinUserIdleSeconds);
+ this._preloadBrowserIdleObserver = null;
+ }
]]>
</destructor>
<field name="_soundPlayingAttrRemovalTimer">0</field>
<field name="_hoverTabTimer">null</field>
</implementation>
<handlers>
@@ -7017,17 +7063,17 @@
// XXXmano: this is a temporary workaround for bug 345399
// We need to manually update the scroll buttons disabled state
// if a tab was inserted to the overflow area or removed from it
// without any scrolling and when the tabbar has already
// overflowed.
this.mTabstrip._updateScrollButtonsDisabledState();
// Preload the next about:newtab if there isn't one already.
- this.tabbrowser._createPreloadBrowser();
+ this.tabbrowser.requestPreloadBrowser();
]]></body>
</method>
<method name="_canAdvanceToTab">
<parameter name="aTab"/>
<body>
<![CDATA[
return !aTab.closing;
--- a/toolkit/modules/Services.jsm
+++ b/toolkit/modules/Services.jsm
@@ -72,16 +72,17 @@ var initTable = {
cache2: ["@mozilla.org/netwerk/cache-storage-service;1", "nsICacheStorageService"],
cpmm: ["@mozilla.org/childprocessmessagemanager;1", "nsIMessageSender"],
console: ["@mozilla.org/consoleservice;1", "nsIConsoleService"],
cookies: ["@mozilla.org/cookiemanager;1", "nsICookieManager2"],
downloads: ["@mozilla.org/download-manager;1", "nsIDownloadManager"],
droppedLinkHandler: ["@mozilla.org/content/dropped-link-handler;1", "nsIDroppedLinkHandler"],
els: ["@mozilla.org/eventlistenerservice;1", "nsIEventListenerService"],
eTLD: ["@mozilla.org/network/effective-tld-service;1", "nsIEffectiveTLDService"],
+ idle: ["@mozilla.org/widget/idleservice;1", "nsIIdleService"],
intl: ["@mozilla.org/mozintl;1", "mozIMozIntl"],
locale: ["@mozilla.org/intl/localeservice;1", "mozILocaleService"],
logins: ["@mozilla.org/login-manager;1", "nsILoginManager"],
obs: ["@mozilla.org/observer-service;1", "nsIObserverService"],
perms: ["@mozilla.org/permissionmanager;1", "nsIPermissionManager"],
prompt: ["@mozilla.org/embedcomp/prompt-service;1", "nsIPromptService"],
scriptloader: ["@mozilla.org/moz/jssubscript-loader;1", "mozIJSSubScriptLoader"],
scriptSecurityManager: ["@mozilla.org/scriptsecuritymanager;1", "nsIScriptSecurityManager"],
--- a/toolkit/modules/tests/xpcshell/test_Services.js
+++ b/toolkit/modules/tests/xpcshell/test_Services.js
@@ -37,16 +37,17 @@ function run_test() {
checkService("dirsvc", Ci.nsIDirectoryService);
checkService("dirsvc", Ci.nsIProperties);
checkService("DOMRequest", Ci.nsIDOMRequestService);
checkService("domStorageManager", Ci.nsIDOMStorageManager);
checkService("downloads", Ci.nsIDownloadManager);
checkService("droppedLinkHandler", Ci.nsIDroppedLinkHandler);
checkService("eTLD", Ci.nsIEffectiveTLDService);
checkService("focus", Ci.nsIFocusManager);
+ checkService("idle", Ci.nsIIdleService);
checkService("io", Ci.nsIIOService);
checkService("io", Ci.nsIIOService2);
checkService("intl", Ci.mozIMozIntl);
checkService("locale", Ci.mozILocaleService);
checkService("logins", Ci.nsILoginManager);
checkService("obs", Ci.nsIObserverService);
checkService("perms", Ci.nsIPermissionManager);
checkService("prefs", Ci.nsIPrefBranch);