Hacker News new | past | comments | ask | show | jobs | submit login
Chrome will aggressively throttle background tabs (strml.net)
811 points by callumlocke on Jan 24, 2017 | hide | past | favorite | 389 comments

I run a real time charting platform for Bitcoin traders (like those using BitMEX) and the app does a lot of updating/refreshing. I recently learned of the visibilitychange API and managed to make huge improvements in the app's performance when running in the background - on the order of ~75% reduction in CPU usage when running in the background. [1]

    var doVisualUpdates = true;

    document.addEventListener('visibilitychange', function(){
      doVisualUpdates = !document.hidden;
Basically, you can use this to determine if your tab is running "in the background" and avoid redrawing/refreshing components to show updates that won't ever be seen.

[1] https://twitter.com/cryptowat_ch/status/817502626896089090

Yeah - that's a really great trick! You can also get this somewhat "for free" by batching updates on `requestAnimationFrame`, which never fires when unfocused.

https://www.npmjs.com/package/visibility is a nice little package that encapsulates some of the browser compat issues, if you have out-of-date clients.

But if you do this, isn't it possible that you'll queue up tons of re-renders that all go off when the tab comes back in focus? I'm thinking of React for example, where you might re-render a component with updated props several times per second. In my case, I've settled on just not re-rendering at all, and then doing so once with the latest props when "visibility" fires again with document.hidden === true.

This is where batched rendering really comes in handy. For example:


The key is, even in your case (with price alerts), you'll still want to tick occasionally, thus the `FORCE_TICK_INTERVAL`.

React's own batching is smart enough to merge the work. For example, before the next tick, one component calls setState() 20 times, another calls it once. Only one rerender will actually be done.

Some more discussion on rAF batching here: https://github.com/petehunt/react-raf-batching/issues/8

I'm not a graphics expert, but one really easy change to make is a pattern like this:

    _needsrender = false;
    function render () {
        _needsrender = true;

    requestAnimationFrame(function hardrender () {
         if (_needsrender) { 
          .... do stuff ....
          _needsrender = false;

Why not limit it to a single render queued with the latest information?

I see this done via debouncing for render operations that happen on repeated events, for instance typing (send query to server, then show matching results in a render of some list).

Yes, this happens in my browser games. When the user clicks back to the tab it fires off all the frames that have been queued up, moving everything in hyperspeed until it's up to date. I don't really mind though, since it's multiplayer it's supposed to catch up but doesn't need to render when unfocused.

Why should the browser rely on the webpage developer to tell it to not redraw things in a tab that isn't the visible one? The browser by default shouldn't redraw content in a tab that isn't visible. This seems like the most obvious thing in the world.

It depends on how you define "Visibility changes".

What might he be talking about? Well, it works something like this...

- The app fetches data from a server.

- The data is processed. This may be cheap, or expensive.

- The DOM is updated.

- The page layout is recomputed.

- The browser window is redrawn.

Certainly, the browser could skip the last step for invisible tabs. It can't skip redoing the layout, as the JS can read the computed layout back out; at most it could do the computation lazily, but that would be extra code and complexity. Everything prior to that step isn't under the browser's control.

The web-app coder could act on every single step in the chain, starting by throttling data fetches.

Because some websites might still need to work when not in focus. E.g. If you are showing animations or videos in a window, but the user wants to answer an IM in another window without interrupting the animations.

But then if you switch windows or tabs, the timer for the animations in the tab that is now invisible can be stopped, surely??

Why redraw an invisible window? In any ordinary paint routine, you query for the invalidated rectangle and only redraw what you must. In the case of pages that are out of view, then nothing needs redrawing.

Processes that are busy doing things they need not (like redrawing on a timer, polling a mouse) is why Apple starting highlighting offenders in macOS (what is hogging the battery??) and why I don't use Chrome on it - it just gobbles power keeping all of those tabs alive.

Hopefully these new changes will help.

OP here. In my case, the CPU saved was mostly React updating its virtual DOM. Yes, the browser doesn't do repaints when the tab is in the background. But there's plenty of other work that is done before repaints when using a library like React.

It doesn't need to do the final step of rendering - but it still needs to reflow the page whenever you change the DOM, because information from that reflow is accessible to javascript.

This is a great tip. To make it compatible with most modern browsers (Chrome, Firefox, Opera, Safari and MS), you'll need to use the following checks:

        if (typeof window.document.hidden !== 'undefined') {
            hidden = 'hidden';
        else if (typeof window.document.msHidden !== 'undefined') {
            hidden = 'msHidden';
        else if (typeof window.document.webkitHidden !== 'undefined') {
            hidden = 'webkitHidden';

        doVisualUpdates = !window.document[hidden];

reference: https://developer.mozilla.org/en-US/docs/Web/API/Page_Visibi...

If you happen to use React, I built a React component that helps you manage this! :) Hopefully it helps a bit! It also reports whether or not a user is idle, such that you can reduce cpu usage during that as well.


i don't know anything about React, but why can't react itself try to manage this?

React is in the business of limiting its API surface, not increasing it. I think they have done a great job of it - libraries like this should exist in userland.

It seems like React could listen for visibilitychange itself to throttle its own events or virtual DOM processing. It wouldn't necessarily need to expose visibilitychange as a library API.

Because there is no sufficient magic for that. App developers have to think about when they do work, how much work they do, and if and when it should be rendered. For any rule you can give, I can give you an example of an app that would break.

In general, the mantra for people who find this tough to fix should be, "Why didn't I use MVC, what a cretin I was!"

For animations/any sort of render loop, you can also make use of the requestAnimationFrame API, which auto-pauses when the tab is out of focus.


Wow that's a great tip, I did not know about that one, but it's going to be very useful for a UI I am about to start working on.

In addition to requestAnimationFrame this could be very handy!

Are there any gotchas you have experienced in using this API that I should look out for?

Just look out for this not being supported and make sure your stuff still works. Eg, document.hidden might be undefined so don't initialize like this:

    doVisualUpdates = (document.hidden === true);

Well, you’d typically want to do visual updates when document.hidden wasn’t true, which would work fine.

He probably meant `(browser.hidden === false)` which wouldn't work if browser.hidden is undefined. Use == instead of === and it will work fine.

No, the opposite of that. If document.hidden === undefined, you don't want to use this optimization at all. What I was saying is, if you initialize doVisualUpdates as "document.hidden === true", in the case where it's undefined, you will never do visual updates.

`!document.hidden` would work, and it’s what most people would normally write already. `document.hidden == false` would not work; `false != undefined`.

On the other hand, it gives us video ads that stop and resume when tabs are switched.

You site is beautiful, very much like HN in the sense of showing lots of information vs following design trends: https://cryptowat.ch/

Very nice.

Hi, this is Alexander. I'm an engineer on Chromium team working on scheduling and on background tab throttling in particular.

Firstly, I want to make clear that we are not shipping this in Chrome 56. We have enabled throttling as an experiment in beta channel to measure impact and collect feedback from web devs. We will aim to ship it in Chrome 57, subject to further feedback.

In response to concerns voiced we will disable aggressive throttling when active websocket connection is present. Tabs playing audio are already unthrottled.

We will also consider more signals to use in exempting a page from this throttling: metatag, pinned tabs, permission to show notifications from user. Please leave a comment in the bug (crbug.com/650594) if you have other suggestions.

Looking forward to your feedback, Alexander.

If a page signals it's desire to opt-out of aggressive throttling, the user should be notified of this, perhaps by an icon in the tab, so that we can either close it or force the throttling.

I'm a laptop user and CPU-hungry background tabs are a huge drain on my battery life. If something is opting out of or otherwise excluded from throttling, I want to know about it.


I agree. I prefer it throttle everything but ask me if a page is important enough. A news site isn't important enough to ask for this but Slack is.

To be honest neither is slack. They've got push notifications through web service workers. What for would they need aggressive background activity?

I'm not saying this to be pedantic, just trying to nip this entitled vendor mentality in the bud. "We're important so give give give without asking." It's a bit what you see with permissions on mobile: the more famous a company is, the more brazen a permission policy they can get away with. It's only tangentially related actual functionality of the app.

This is not about you personally, by the way, but about vendors. You just shouldn't let them get away with it. Even if they're slack :)


The user ultimately needs to retain control. And I'm especially interested in the exception for audio - that really should be user-controllable, otherwise it just encourages annoying page authors to be even more annoying.

The audio thing works because there is an obvious icon in the tab bar that shows the source of audio, so if developers use it in an annoying way the user can easily respond appropriately.

Just wait until background junk audio is included in a framework. We'll never be rid of it.

I already stopped visiting sites that had background audio autoplay. I don't think sites will get more traffic if they pick that up.

I think you'll have to wait a long time. I doubt it'll ever happen.

There is now an incentive to do this, so it will happen. Same as "with popup blockers everywhere, popups are now replaced with HTML5 above-content layers."

Note that you can always mute a tab in Chrome, which I suspect would remove the exemption as well.

I wouldn't be so sure. I'd be interested in a definitive answer.

Yes, muting a page means that this page is throttled again.

I don't want to switch to slack and wait several seconds before messages update. I'd rather the state be updated beforehand asynchronously.

While I agree with you in theory, this will only help a small fraction of us techie users. The average user is going to see a new, weird icon on their eBay Auction tab and call their computer company to ask them what it is and if they're being hacked.

When I did support for Apple Care, every single update if it had new or extra icons we always got lots of calls like this.

I'm sure some good UX could alleviate this. Maybe a spinning gear icon? Maybe a battery draining animation? Something to signify, 'this tab is doing some heavy lifting right now'.

It's actually a pretty rational response for someone who is only moderately aware of what is going on in their computer. If they are aware that malware and adware can cause unwanted changes on their computer, perhaps because they've been bitten before, then a new icon -- even one that is easily interpreted (which this one would not be) -- looks scary.

Icon: "speaker" for audio sites, icon: "Power cable" for background power usage?

Lightning bolt / Zap icon

Already used for amp pages, would be confusing. The power cord is probably the right symbol, probably with an explanation if you hover over it.

Then you have a fav icon, the page title, possibly a mute icon, a close icon and a throttle icon? The mute icon and page title aren't visible anymore as it is with many tabs open, so adding another icon doesn't sound like a good idea, especially if visibility is important.

I'd like to see the user better informed of hot (active) tabs. Just like there's an audio icon to help the user track down which tab is making noise, there should also be some mechanism to let the user know that a tab is more active than usual.

I'd recommend a different background color for the tab, except that I'd also like to see (sign in) profiles have distinct background colors to aid the user in keeping their profiles straight.

Color change on the tab would be nice - maybe have it slowly grow more red (and perhaps add an option to change the color as well - for colorblind folks) - then start blinking - then burst into flame...

I think Samsung tried that approach

While I've only seen it once, when I looked at it upon learning of its existence- the Chrome 'task manager' might show CPU usage of each tab. When I look at all the chrome.exe processes in the Windows Task Manager, the CPU usage is clear, but I can never tell which process is which tab. Something like a glowing tab coloration animation would be an unobtrusive informational thing, that would work even when tabs are pinned & too tiny to display a meter type thing inside them. Maybe if there could be a 'pause' button that appears on hover to allow this throttling to be engaged or not. Sounds like something to this extent might be a successful extension, then maybe if it sees broad adoption it could be implemented permanently.

No: the Chrome task manager shows activity per process, not per tab; processes typically have many many tabs lumped together (which undermines the security advantage, particularly as commonly-opened tabs like e-mail tend to end up having at least one instance open in every single process). You can't use this feature to figure out which tabs are using CPU unless you are barely using the web browser in the first place.

Whether or not tabs are in a new process depends on how it was opened. For example, opening a new tab with a control-click or middle-click will result in the new tab share a process with the original, however, right-clicking and selecting "Open in new tab" will result in the new tab having its own process.

I know this, and have even complained about it in the past to Chrome engineers (as it allows an attacker way too much control over getting security sensitive tabs into the same process, further weakening the way overstated security benefits of having separate renderer processes, which is often muddled together with the actual/real benefit of separating processes by capability, as with rendering, networking, windowing, plugins, etc.), but there is also a limited number of processes: as I believe the default is 35, if you have more than 35 tabs open across all windows you are guaranteed to have some tabs sharing a process (by pidgeon hole principle).

Realistically, you just can't use the Chrome task manager to find slow tabs :/. I'd argue that Firefox's recent work in about:performance is actually more useful for this purpose (though isn't very good at dealing with large numbers of tabs that are each using only a small amount of CPU; the real solution to that, though, should just be tab suspension).

This made me picture one of the old school nintendo games where your character starts sprouting flames when on a hot streak. There are times I would like to see flames flying off tabs that are pegging my cpu.

Perhaps the icon could be a spinning fan?

This would be great - and the measurements used to do this throttling could be used to populate that data!

Two outstanding suggestions

> In response to concerns voiced we will disable aggressive throttling when active websocket connection is present. Tabs playing audio are already unthrottled.

The pages that are most aggressive in being a drain on resources, in my experience, are also using websockets to constantly load in new advertising and JavaScript and other garbage. Just "the page has a WS open" should not be enough to keep a page unthrottled without providing the user a chance to change that behavior.

Pinning a tab should disable throttling. Gives user straightforward control over which tabs are important.

I second this. I'm generally a fan of efforts to reduce the CPU usage of background tabs (as one who constantly finds himself with an embarrassing number of open tabs), but I need to be able to control which tabs I absolutely don't want throttled.

Not the greatest solution, considering Pinning isn't documented anywhere and most Chrome users have no idea it exists. Which is a shame, as pinning is probably my favorite browser feature.

>Not the greatest solution, considering Pinning isn't documented anywhere and most Chrome users have no idea it exists. -- I might say this is precisely why it'd be smart mode of control: Tying a power user-ish granular feature (throttling) to another power user feature (pinning) seems like a bit of self-selective optimization, while being quite elegant in its simplicity.

So, for me, +1 for pinned tabs != throttled.

I'd use Pinning a lot more if it didn't shrink the tab down to its Favicon size. Wish it would also prevent you from closing the tab.

Interestingly, I'd never use pinning if it didn't shrink the tab down. I never have any trouble with keeping my tabs ordered, so the main value pinning gives me is the shrinking.

Same here. The shrinking keeps my tabs so much more organized.

FYI: You can still close the tab, just not by clicking the (no longer visible) X. This may not fit your use case, but then again it might (I can't remember the last time I closed a tab by clicking instead of with ctrl+w).

he is saying that he wishing pinning tabs _prevented_ the tab from being closed (as opera does). I have closed pinned tabs my mistake before (ctrl+w too many times) and I agree.

Oh, my mistake

+1. I just now found out about it. Tried it, saw the tab reduced to a favicon, and will probably never use it till that's fixed. Especially with how a Gmail Tab blinks when I get a hangout message.

The "reduce to favicon" is my favorite part of pinned tabs: I pin all my slack tabs and other messaging tabs and just watch for the blue dot indicating activity and/or the red circle that indicates a private message (on slack)

> Especially with how a Gmail Tab blinks when I get a hangout message.

The pinned tab for GMail has a blue dot for "attention needed". Though this is suboptimal because I think it represents both IMs and new mail.

Are you sure that's not an extension? On macOS, at least, it's a very subtle gradient color change animation that's hard to notice.

I get a blue dot on my mac

Also there are some sites that don't work well with pinning, including G Suite. I'd love to have pinned tabs for work email, work calendar, personal email, and personal calendar. But every time my session expires, they all get redirected to login pages.

Am I the only one who uses pinning as pseudo-bookmarks? I would rather my pinned tabs be throttled more rather than less.

I do that too, sort of. My pinned tabs are either VK/Facebook messenger, or things I plan on getting to later (interesting software to install, movies to watch, ...)

That's funny... for me the pinned tabs are the ones that are always open (email, Slack, Spotify).

Am I the only one that finds pinning extremely buggy? I try it every year or two and always have the same result: pinned tabs work great at first, but eventually enter a state where tabs cannot be completely unpinned.

Unpinning and restarting my browser brings them right back in pinned state, and it seems like nothing I do short of reinstalling my browser profile corrects this.

I've seen this happen on multiple machines, so I feel like it can't just be me.

I like the idea of pinned tab, but since they cannot be moved freely it is only halfway useful for me.

Including me, thanks for the tip! First time I've ever heard of this feature.

Pinned tabs definitely should be excluded from throttling. Pinning tab for me usually means that I want to keep track of something, which usually is my email, chat client, etc. I don't want to be notified about new email on my phone before I get that notification on PC, which is already happening too often. That's just unnecessary hassle.

Though I'm not sure how popular this feature is and I would vote for other ways to turn throttling off, especially for those which prompt user about it.

> We will also consider more signals to use in exempting a page from this throttling

The main problems I have with background tabs and resource use is advertising iframes on otherwise inert pages. iflscience.com and sometimes imgur.com are two notable offenders here in my experience.

Advertisers will opt of anything that might throttle their content whether they need to or not, without testing if they need to, just in case. so if there is an opt out I expect it to be abused such that this pain point will not go away.

As well as asking if a particular domain should be allowed to unthrottle itself as others have suggested (or instead of if there is a fear that extra UI interactions will confuse the user) perhaps you could only allow it if the top level frame also opts out? This would give control back to the main page maintainer and if used in combination with the prompts could confuse less technical users less (the request for unthrottling comes from a recognised name like iflscience.com not content.idofmachineinfarm.r438957432t43.somecompanyyouveneverheardof.com)

> disable aggressive throttling when active websocket connection is present.

How is "active" defined here? I foresee advertisers opening a websocket that does as little as possible in order to get a prompt-less lifting of the throttle...

> Tabs playing audio are already unthrottled

I'd love to reverse this and punish tabs that play audio in the background! (or to allow for genuinely useful uses, such as message alerts, punish those that play more then 5 seconds of audio in a minute, unless tey are whitelisted).

I think the heart of it is that "using my resources in the background" needs to be 100% opt-in. All webpages should be frozen and use 0 CPU/RAM unless the user grants them permission. I can think of only a handful of sites I would grant this permission to - mainly "apps" such as Google Inbox, Slack etc.

Tabs playing audio will include a lot of people listening to music on youtube.

Exactly. There are a few obvious things that want to be allowed and many others (sites playing adverts and such) that don't.

White-listing youtube would be one click for ever (potentially) and the same for other similar sites (vimeo, maybe facebook, ...) - in fact not even that as common sites like that could be on the list by default (as long as there is an easy way to de-list them).

There should be a way to force-enable this for tabs, even foreground tabs. Some sites are just terrible.

I'd also appreciate it if nothing the website can do can override that. If I mute the audio, then it shouldn't be a signal, and you'll want to avoid using signals which the websites can trigger without user action.

Honestly, I'd prefer if there was some way to entirely suspend event processing on a tab, or at least timers.

Hi Alex, I appreciate your work. My macbook air is getting pretty slow and this is the best free performance boost I could ask for. keep up the good work.

> In response to concerns voiced we will disable aggressive throttling when active websocket connection is present.

Does this extend to SSE?

+1 for active SSE connection as an another signal

+1 for SSE!

Is this some sort of reaction to Microsoft's over the top desktop ads campaign against Chrome?

Make no mistake, I do believe Chrome could benefit from this, and I do believe what Microsoft is doing is skirting the edge between ethical and non-ethical (okay, I think it's sleazy). But it just seems like a curious coincidence.

There should be a way to opt out of this per domain, the way a user opts into Notifications API, Webcam API, etc. A website should be able to ask permission to not be throttled this aggressively.

In addition to automatically inferred signals, it would be great to give the user optional complete control over throttling as well at a per-tab level. I.e. a switch somewhere that user can freely enable/disable for a given tab to mark it throttled vs. unthrottled, whatever the right terminology would be.

> permission to show notifications from user

I provide notification access to news sites, not sites I want constantly burning my CPU. This is "throttling", not "100% suspending forever", right? There's no good reason to give more CPU to these tabs that might be occasionally wanting to tell me something from the background: as they are in the background that's the only thing they should be doing, and if they are currently doing other things they should have a strong incentive to stop doing all that other stuff when they detect going into the background: there should be no exemption for tabs with notification access.

User should have a way to enforce throttling on all tabs. e.g. I always have my iPhone on low power mode. Its the users choice, not the developers. As much as I hate saying that as a developer.

As an example - I never listen to audio/video in a background tab, but I have to suffer battery loss because of features that I have no plans to use.

The Apple model of asking user for permission when it notices that a background app is reading your location could be a good model to follow. That way, when you notice a frequently battery hogging domain in the background, even if it uses web sockets, etc., you still prompt the user to throttle.

Pinning a tab has the side-effect of shrinking its title bar to just the icon. I use the text on there to communicate alerts / information to users. (Maybe pinned will enlarge if document.title is changed or something don't know never use it). So hopefully there is another way. To me `site settings` `Throttle this site when in the background, Warning: this may slow your machine and consume additional battery resources`

To me the fundamental issue is one of user control. If the user wants the site to run in the background, great. However a lot of times they don't even know that it is and, surprise! the battery is drained, or everything is running slow and it's time to press shift+esc and stare at the jumping percentages in the task manager.

So to that end, communicating what's going on to the users, is I think pretty important so hopefully:

* A Visual Indicator on the tab, similar in spirit to the speaker or red recording circle, that conveys

  1. Tab is fully utilizing its throttle.

  2. Tab has throttling disabled by user-request.
And then to give users control:

* The ability via `site settings` to disable the throttling, however if a site is using excessive background resources, some sort of ui should show indicate such.

(A lot of this would be almost trivial by showing little cpu use bars, with a line where the throttle is, but it might look kind of ugly)

Even though this is going to break some of my apps, I can see a greater good here, and I am 100% for helping out with battery life, and preventing my machine from being some sort of ad network computation shard. So I am fine with this being the default option even though it will break apps I have written. They are mostly in house tools so as long as I can instruct users to override the throttle, provided I am given that option, which it seems like I will be.

I would figure that for larger more public facing devs, the experience might be a bit more tedious. Perhaps a unthrottled-background permission request API can be done. And hopefully for legacy sites that won't be updated, the visual indicators above will clue users in as to fact that the browser is throttling the site. Perhaps ugh I hate even suggesting this, a nag bar could pop up when the user navigates back to the tab to inform them that the site was aggressively throttled.

Anyhow, I am glad you guys are getting out ahead of this, I think this stuff is going to get worse as sites seek to run more code on our machines in ways we cannot easily discern. So I actually don't like that workers / websockets / audio work around aggressive throttling, because the bad actors are just going to use that to burn cpu in the background without the users consent. Hopefully if executed well, with a helpful ui, this can be used to stop any unwanted and often unseen but still felt cpu waste while allowing sites the user actually does rely on to continue working.

ps, I'll cross post this to your tracker as well as you requested, I just know that leaving it here will get more eyeballs from a larger community to give their feedback as well.

Speaking of audio tabs, the mute setting should be inherited. If I have a muted tab and then open a link in a new tab, I should get a muted tab.

+1 for pinned tabs

It's awesome to see Chrome trying to improve performance for people with many tabs open, which is many of us.

I use a LOT of tabs, and the best plugin has been The Great Suspender. Highly recommend it for anyone who wants memory & CPU back and keeps many tabs/windows open at once: https://chrome.google.com/webstore/detail/the-great-suspende...

I meet many tab hoarders (always open a new one, never close any, ending up with hundrets), but just can't wrap my head around it!

I hate having more than 6-7 simultaneously open because it gets increasingly harder to keep an overview of what you're doing. The same applies for IDE tabs or windows. Too much of them and finding the right one becomes increasingly hard, and losing the thread more likely.

When I am doing coding work, I often have a ton of tabs open. I will keep different documentation tabs open to the relevant sections. I will keep some tabs with answers on StackOverflow.

My open tabs are kinda like my working memory. I could close them and reopen them as needed, but it is easier to just click a tab then to try to find the thing again. In addition, sometimes the pages I am looking at have dynamic navigation, and closing and reopening the page will require a good deal of navigation to find the section I was looking at. Plus, the overall time to reload the content, where if I just have the tab open there is no download time.

Also, the tab icons help me remember what I was looking at. I will often keep tabs open for what I wanted to read later.

I don't know whether that exists for chrome too, but for firefox I find tree-style-tabs very useful to organize my open tabs when developing. A top-level tab for the different topics (e.g. one toplevel tab for a project's github issues, one each for the libraries I'm using, one for news,...). Then when switching tasks I can just minimize those.

I'm using tabs in exactly the same way. For the read later tabs something like http://www.tabsnooze.com/ might help. I haven't tried it yet, but it sounds good. "Save to Inbox" is another option.

Yeah, I basically do the same thing, but that hardly ever requires 10 tabs for me. When that happens, finding tabs becomes especially harder once their width starts to shrink.

As for read-later, I usually pull them into the bookmarks bar (top level, directly visible) to free up some space.

I use one-tab.com; works fantastically for me. Not a huge stretch to say it changed my life.

For what it's worth, there's a similar feature currently available in Firefox Test Pilot: https://testpilot.firefox.com/experiments/tab-center

Are you taking about tab center? That thingy had a number of issues last I checked, I especially remember there was something weird about the layout of it. I think it extended all the way up on the side of the menu bar. This looked weird to me (and I think UI is overrated) and makes the toolbars slide when I open/close the tab drawer.

I'd recommend using one of the extensions instead.

OneTab can make a huge difference. And being able to do a quick find on your list of old tabs certainly makes things easier for those of us who are, uh, a little over the top when it comes to opening tabs.

The only bad thing is realizing you have a couple hundred old tabs to go through and delete. They really add up over time.

Thanks, looks interesting! Link: http://www.one-tab.com/

One-tab doesn't sync or let you backup to another source (e.g. Dropbox). I use it, but taking manual backups is a pain.

> June 2016 Update: We're currently working on new features including an option for multi-PC cloud sync. This has taken quite a few months to put together due to the huge number of extension users that the cloud sync will need to support. Thank you for all of your feature suggestions, please keep the feedback coming. -OneTab

I used this years ago, then tried to cure myself of tabs by forcing myself away from it. It didn't take, and I completely forgot about this, going back to The Great Suspender (which is also great). Thanks for reminding me about this!

With Firefox you just open a new one and start typing part of the title or url and it finds the tab.

If I want to add a new tab instead of finding the old I can press shift (IIRC).

Bookmarks, man!

As I said in my comment, bookmarks don't work for sites with dynamic navigation - you won't end up in the same place when you load the page from a bookmark.

In addition, you have to take the time for the page to load, you have to delete the bookmark later if you dont want to clutter up your bookmarks, etc.

There might be a more effective way to accomplish what I do with many tabs, but it works for me at the moment so I haven't attempted to find a browser plugin or extension to change the behavior.

I use many tabs as a stack of pages when debugging, researching, or reading aggregate news feeds (reddit, hn). It usually starts with a Google search or two, in which I open all links I think _might_ be relevant based off of what information google can provide me from the results page.

From there I read through each and open any further tabs if anything is linked too in the text (I hardly ever actually click navigate, it's most always a new tab). Generally this only goes about 3 deep (search, first page, sub links). I will close any pages that I find have no useful information, but if there is anything I think might be useful in the next 30 minutes I just leave it open. I do this for each of the results I originally opened. Somewhere in the 7-15 tabs generally is the answer I'm looking for or at least there is enough information I can answer my question. If any link is particularly beneficial, I will bookmark it. Generally the time span I have a large number of tabs open is no more than an hour before I'm finished and close everything out.

Chrome handles this nicely, if you are on a page and open a tab, it will place the new tab next to the current tab, instead of at the end of the tab list. Some sort of tree tab view would probably work much better for this, but Chromes behavior isn't bad for what I do.

I have this pattern. It plays really well with the 'close all tabs to the right' menu option, because once you've found whatever you were looking for, you can nuke all the leftover tabs.

What I'd really like, though, is a 'close all descendant tabs' option.

For tree tab view, I suggest looking at Tabs Outliner. I can't use Chrome without it anymore.

Not if you use Tree Style Tabs. I've been using it for years and I have no idea how other people can efficiently browse the web without it.

Tree Style Tabs is a nice idea, but I found the balance of aesthetic and speed for me to be with pressing Ctrl+L and then inputting a few letters relating to the open tab I seek, then just pressing Enter and switching to the tab.

I don't understand why this seems to only be a thing in Firefox - it's awesome.

I remember looking for a similar Chrome extension, but I think Chrome doesn't provide the appropriate hooks, or something.

Interestingly, Mozilla is trying to move in the same direction by supporting the same extension APIs as Chrome because they are more maintainable/secure/universal/performant but continue to struggle with adoption because things like the Tree Style Tabs extension are not possible with that api https://blog.mozilla.org/addons/2015/08/21/the-future-of-dev...

And it sucks because it's the only reason I'm not moving to Chrome -- Tree Style Tab.

You can also type % followed by the query in the search bar to only search within open tabs.

How do you get this feature? I know I've seen it, but it's not doing it on Mac Chrome.

Firefox. Maybe chrome has it as well, but Firefox does look like Chrome if you're not looking closely these days.

Hmm, looks interesting. I've tried out several tools for organizing tabs, but none of them really worked as well as aggressive manual "garbage collection" for me. Usually the problem was that switching between groups (or whatever concept) was too complicated, or part of the tabs were hidden too much. Maybe I should give this one a try.

With Tree Style Tabs I just got to the same level of disorder with even more tabs open. It didn't actually help my behavior :)

Even by using nested tabs?

I use my tabs as a task list. I close them once I have read the page, taken action on the knowledge in the page or decided it was too stale to matter anymore.

If you have to deal with a lot of task switching, blindly closing browser tabs would be a huge waste of time. You can individually check each tab before closing the ones you don't need, but that takes time and cognitive load.

So I leave them open until the computer can't handle it.

Finding the right tab is much harder if you got a whole bunch of them.

I always close them, most aren't needed for a long time.

But if I need stuff I closed I just hit 'reopen closed tab' a few times.

Much easier in Firefox since you just start typing the name of the site then choose to switch to that tab from the drop-down menu. Or you can pick it off the (down-arrow) drop-down list of your tabs, or just use the mouse-wheel to scroll quickly through all the tab headings....

I typically have 100 or so tabs in Firefox. I did get over 600 once, but that's too many ;-)

Well, it's quite similar to garbage collection, or disk defragmentation. It comes with some cost but improves performance, so it's all about finding the best trade-off.

I've given up on navigation.

I use my tabs like a generational garbage collector. Tabs to the left of the current tab are processed, tabs on the right are to-be-processed. I'll go to a page like reddit or HN and spin off a dozen tabs of things to read. Then I'll go through one by one and either process, delay or close.

Once I reach about 250 - 300 tabs, I'll do a longer generation sweep and go through all the tabs and try to get it down to less than 100 or so.

Basically, I'm never in need of finding any specific tab. If I want the content from that tab, I'll just open a new one and navigate back to that point. The tabs are really a lightweight to-read list.

Same here, unless I am piling search results, which will be reviewed right afterwards, I hardly have more than five open.

On the other hand I rather use native apps, when given the option.

Which I also only keep the ones for the task at hand open.

I am a tab hoarder I guess. I use them to organize my work. Every window is a project (right now I have 5 of them) and all the tabs (20-30) are mostly resources I need to fulfill them. If I have completed a project or decided to stop working on it I close the window and get rid of all project related pages at once.

I don't use favorites or bookmarks because usually I don't need a link permanently.

Edit: I actively try not to get too many. If it starts to hide the title/favicon completely I start to close them again until I can recognize them by title without clicking through them.

Probably the same thinking that goes with storing everything on the desktop or having many windows open.

I'm more of a less is more guy, when it comes to windows/tabs.

Tabs are a todo list. I've currently got two pinned tabs open, JIRA and bitbucket tabs that act as placeholders, one unfinished email, one spotify playlist for work, one podcast, and 6 articles to read. And that's only because I recently restarted Chrome. I can easily have 20+ tabs open if Chrome has been running for a week or two.

I use it like a kind of mental stack or breadcrumb. The tabs most relevant to my current task are on the right, usually no more than three. The rest of the tabs is how I got there, occasionally serving as references. Once I get to the point of making it hard to tell one from the other I tend to do a garbage collection sweep. Sometimes, when switching context, I just reopen Chrome to clear the stack.

Incidentally, the note papers floating around on my desk works in a similar way, although they are more of an unordered set. Only one or two are relevant, the rest were helpful at some point but no longer are. Cleaning my table usually results in me dumping the whole thing in the dustbin.

> overview

Why do you need an overview? It's like stack frames: you can limit your scope to what you're currently doing. The other tabs represent stuff that's "parked" and you aspire to come back to.

(This is why tabs are better than windows for this, because they maintain a linear order while most systems will re-order window order if you visit the windows)

My tab-opening habits predate tabs, because I was raised on Netscape Navigator with a modem using "open in new window" instead. I would read down a page and open interesting-looking hyperlinks in the background, so I didn't have to wait for them to load. Another advantage of this technique on modems was that I could close down the line and carry on reading.

For me, it's more that I use my tabs as reminders for things I need to do or things I want to read (I know, this is a pretty bad system, and I try to use a better to do list and tools like Pocket on top of tabs, but I always seem to drift back to just tabs simply because it's the lowest effort system for me to ensure I remember). If I'm working, I'll generally just open a new window and keep the tabs I'm actively using there and get to the backlog later.

I tend to lean towards tab hoarding. I use Tab Corral to automatically close out old tabs, which works out pretty well. Rather than having to evaluate whether I still need a certain tab up, it quietly closes it after a bit, usually once I've forgotten about it.

The tabs are transient todo list. This is something I need to finish researching, this is a documentation to what I'm working on, these are 3 great articled I want to read in the evening.

The combo of The Great Suspender + Session Buddy makes tab management so much better, and easier on resources.

Leave open the tabs you know you'll need soon(ish) and let the Great Suspender throttle them, and save (then close) groups of tabs/windows you won't need right away using Session Buddy.


Seconded. Chrome used to crash ~1/month on me but ever since I started using The Great Suspender I haven't had a single incident and it's been well over a year.

+1 recommendation for The Great Suspender. Works like a charm, noticeable difference on overall system performance.

Any experience on how it compared to The Great Discarder from the same dev? https://chrome.google.com/webstore/detail/the-great-discarde...

The description for that extension in the store explains it pretty well:


Advantages over The Great Suspender:

- More memory savings

- Compatible with chrome tab syncing

- Super lightweight extension that uses no content scripts or persistent background scripts

Disadvantages over The Great Suspender:

- No visibility on which tabs have been suspended

- Unable to prevent a tab from reloading when it gains focus


Is there anything that does the opposite of this? A lot of our current tests run in a browser window, and generally I leave it in the background as I don't want to stare at my tests running. However, when they are backgrounded they slow down and sometimes fail due to timeouts. I haven't actually tried, but does opening a new window get around this even if it does not have focus?

Unfortunately, I find a lot of sites don't play nice with The Great Suspender. Lots of js-heavy sites would break when they were "resumed", resulting in my place in an article/podcast/video/etc being lost. I'm glad Google is addressing the issue; hopefully they'll do so in a way that's more transparent to the user.

Just white-list those sites.

same here using The great suspender, how does this throttle thing relate to the suspender?

If you are using The Great Suspender, chances are that background tabs are going to be fully suspended so the aggressive throttling isn't even needed.

tl;dr - Great suspender is even "more aggressive" than the outlined throttling, as it fully suspends the page and returns all CPU and RAM to you, so it's a great solution for people interested in throttling background tabs.

I use the GS and love it however I'm not sure it returns even most of the ram. Maybe 50pc. Certainly Javascript CPU usage is reduced however chrome seems to slow down based on how many tabs you have open regardless of what they have in them.

Yeah I just use this. I works very well. Its annoying how much JavaScript pages are running now days.

Fantastic tip, thx!

I like the change as a general idea but there obviously needs to be a manual override. Like, I don't want websites to access my camera without permission but obviously I want to allow some websites to do that. A similar permission could be used here and is perfectly backwards compatible:

1. a tab exceeds its quota and throttling kicks in;

2. you visit the tab to check why it stopped working;

3. you get a permission pop up (like all others) once you visit the tab again, asking you whether you want to allow it unlimited resource usage, noting that it'll decrease battery life of your device.

Pinned tabs would be an easy solution for this.

"Don't throttle pinned tabs"

A common use-case is tabs that are streaming music. I'm not sure if most users are even aware of pinned tabs.

They are making an exception for tabs that are playing audio.

You can see the discussion back and forth, here: https://groups.google.com/a/chromium.org/forum/#!topic/blink...

I can see where that will end up though. Everyone who's app was broken by this change will start playing zero volume audio, then the exception will be yanked back.

With the web poised to be the new platform for applications, there really needs to be some more thought put into how to accomplish that goal. The chrome devs already sunset some solutions in that space, like the HTML5 app cache. Now this. Nobody likes a constantly moving target.

No tab should get the audio exception unless it started playing audio while I was looking at it. (reopen yesterdays tabs counts as looking at it...) If you play audio to get around throttling - you should get zero CPU, not just throttled. If you have work to do in the background that is fine - there is legitimate work to do. However once you are playing audio it must mean the other work is done.

What do I know though? I don't normally listen to audio on the web...

I think they are somewhat stuck with conflicting goals. Online games, for example, play audio while doing other work. But it's probably reasonable to pause everything, including the audio, if you move away from the tab.

On the other hand, if they are using Pandora or similar, the end user probably wants the background tab playing and doing other work (showing current album cover art or whatever so it's there if you switch back to that tab).

allow_exception = volume < audible_threshold

Super high pitch noise would get through?

I use pinned tabs extensively and I prefer that they are throttled even more aggressively than standard open tabs. As long as streaming doesn't break.

I have an option set in FF's about:config that disables loading of my pinned tabs on startup, so I regularly keep 200-300 tabs open and only activate the ones I need.

Sometimes it takes weeks to clear my tabs because I barely see a performance hit from having so many open.

Unfortunately this doesn't seem to be the way most users are using pinned tabs. Check out the great suspender. The only tabs it does not freeze are the pinned tabs.

Extending that functionality to throttling seems natural to me.

It looks cool. Browser memory isn't too much of an issue for me because I run NoScript and uMatrix and thus most of the tabs I have open aren't each running an instance of Google Analytics and stuff like that.

It still drives me nuts there's no keyboard shortcut for it. `Command + Shift + P` would be sweeeeeeet.

It is silly to need an extension for this, but I don't know what I would do without `Command + Shift + X`


Awesome. Thanks!

I was not, what a great feature!

didn't they remove pinned tabs a while back, and then re-add them?

While this is elegant, its still dangerous. There are online payments that could check whether your booking is complete in the background by periodically firing ajax calls, bulk updates or uploads, etc.

If those sites are using more than 10% of a CPU to do it, then they've made a catastrophic error, and I'd be glad for Chrome to protect my battery from that.

The business decisions a website makes are none of my business, and if they want to use a polling model for billing because $REASONS then that's their problem.

How is that relevant to throttling?

I don't want to have to pin every single tab I want unthrottled - that's a mixing/piggybacking of otherwise orthogonal concerns. Just make it a separate option I can set per tab.

This would be great. At the very least, I'd like the power to un-throttle a tab myself if I decide to do so - even if there's no prompt, it's important to me that I can let a process run full-speed in the background. Losing that would actually decrease the value of Chrome quite a bit for me.

It could also be a permission granted to a Progressive Web App once the user has decided to install it.

Or just ask for the permission when you first open the page, the same way uber asks for your location.

www.foobar.com wants to:

"Run in the background unthrottled"

The amount of people that will understand what that means is not very substantial. Usually asking for more permissions confuses users as well, people get permission fatigue.

i don't think that would work.

request for location doesn't require the page to explicitly indicate a desire, the request is triggered if the page attempts to use the location services of the JS API. sites that want to run unthrottled can't be identified simply by the usage of a certain API, so the developer would need to add something explicitly to their markup to indicate the desire.

i want control over the feature regardless of whether or not the site's developer deems it appropriate.

I really don't want EVERY website I visit to do this (at least in a pop up).

That's less "backward compatible" than the suggestion to pop up a dialog on switching to the page, because the page needs to know to ask for the permission.

I'm not sure if that's a good thing or a bad thing. After all, backward compatibility is how we got the semantics of an alert() dialog stopping all JS execution.

These days, due to my annoyance with pages reloading themselves when switching to a tab, I'm really not interested in packing more functionality into the whole tab switching mechanism. Like the back button, it should not be visible to web developers.

Every website would start showing such popup. Now (if you have enabled Javascript) many sites show popup to allow notifications the moment you open them. That is annoying when you search for something in Google and have to click "No" for every new page opened.

Seems like the current solution they're advocating for is for sites to do background processing in a [Worker][1].

This seems like a step towards the way things work with mobile apps currently, where the app's main thread gets suspended when its not in the foreground, and background processing happens in separate threads which the user has some degree of control over.

Edit: I meant regular `Worker`s, not `ServiceWorker`s.

[1]: https://developer.mozilla.org/en-US/docs/Web/API/Worker

Except it should probably be web workers that are unthrottled. However, in the current implementation Web workers do get throttled. Service workers are supposed to be for networking and offline applications, not doing cpu related things. As such, service worker lifetimes are really messy since they don't have real guarantees as to if they will randomly restart.

I am having a hard time finding where it states that web workers are treated the same as threads managing visual content. Currently timers in background threads are throttled to 1sec minimum interval however workers are not bound by this constraint. I may just be missing something, but I sure hope not. This would adversely impact many games and applications rendering many of them unusable without the web worker exclusion.

Yeah, sorry. I keep conflating service workers with the larger concept of web workers. For more intensive tasks you'd definitely use a regular dedicated worker, not a service worker.

Far enough down this road, we're just reimplementing 'renice'.

... which may actually be the right solution.


I swear to god if I see anything mentioning a battery on a desktop machine with no battery...

There's no way to know whether or not it has a battery. Maybe it's on a UPS, for example.

All I know is that my desktop runs at about 70W idle vs. 450W fully-loaded. Unnecessary use of the CPU wastes money regardless of whether or not you're using that money to charge a battery.

Sites can get your battery level from the browser.

IIRC, most of the browsers are going to do away with this functionality soon, however.

Even on a desktop machine, you don't want tabs spinning in the background (using electricity) if you don't need the work being done. That's bad for your wallet and bad for the environment.

Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact