Currently, Firefox Nightly uses one process for the browser UI and a separate process for web content. However, one web content process is shared by all tabs. So slow JavaScript in one tab won't block the browser UI, but it will block web content in other tabs.

You can change this by increasing the "dom.ipc.processCount" preference in about:config, but there are still some known bugs with multiple content processes in desktop Firefox. There will be more work on multiple content processes in the future.

There is a lot of old cruft in its web engine "gecko" (http://en.wikipedia.org/wiki/Gecko_(software) , http://en.wikipedia.org/wiki/XUL , http://en.wikipedia.org/wiki/XPCOM). Many addons are XUL based and have had problems with the multi process mode. In 1-2 years hopefully Servo is ready combined with a simple HTML based UI to do what Firefox/Firebird/Phoenix did with Mozilla Suite: http://en.wikipedia.org/wiki/History_of_Firefox#Naming

And yet if you read the comments in this thread there are still people arguing against its necessity.

Chrome also groups multiple tabs on single process, based on a number of factors: https://www.chromium.org/developers/design-documents/process...

IE7 or IE8 introduced multi-process sandbox in Vista (not on XP). Afterwards, Google did the same with their first Chrome release.

In both IE 8-11 and Chrome 1+ there are several tabs per sub-process. Chrome comes even with its own "Taskmanager" where you can see which tab sits in which process and how many resources it takes. You can find the Taskmanager in the Chrome's "Tools" sub-menu.

Buggy code shouldn't exist. Buggy code exists. When the buggy code in question isn't written by the browser then it's up to the browser to properly deal with that buggy code. Firefox doesn't. Other browsers do, but Firefox doesn't. Thus as a user I can either use Firefox and have a bad time or not use Firefox and have a good time. The choice is easy.

Maybe Mozilla is planning for the future better than all others. Perhaps in another 10 years Firefox won't be a shitty user experience. I will gladly switch if that becomes the case. I'm not holding my breath.

It's not that it's a full decade behind the curve, it's a decade behind where your perceived curve. There are advantages and disadvantages to both monolithic kernel and microkernel operating systems^H^H^H^H^H^H^H^H^H^H^H^H^H^H^H^H^H^H browsers.

Not for me, I have barely had any crashes or freezes with Chrom(ium).

There's some interesting talk about that in mozilla.dev.platform: https://groups.google.com/forum/#!topic/mozilla.dev.platform...

Back in 2013 the increase from one process to two processes were 10MB.

https://billmccloskey.wordpress.com/2013/12/05/multiprocess-...

This is the exact opposite of my experience with current nightly. The browser feels very snappy and I have yet to see memory usage climb above ~350 MB with a multitude of JavaScript heavy tabs open. (Although I don't know if e10s is directly responsible for the latter.)

Thanks for the link. It's almost certainly one of my addons that's causing the trouble, but I like my addons!

Yes, and I believe that before the layout didn't happen concurrently with other stuff in the browser. It was called on a change and the rest of processing waited. Is that not right?

Uninstall plug-ins like Flash, and Java or at least set them to block by default. Get µBlock¹ to block unwanted content. Find better sites to visit.

You could also try one of the BarTab extensions² and Tab Groups³ to only keep the sites you use loaded.

1: https://addons.mozilla.org/en-US/firefox/addon/ublock/

2: https://addons.mozilla.org/en-US/firefox/search/?q=bartab

3: https://support.mozilla.org/en-US/kb/tab-groups-organize-tab...

Doing any kind of web research for work is effectively a breadth-first tree traversal. Remembering all the higher level nodes, when you're ready to go the next level deep, would be a nightmare. My brain couldn't handle that, but tabs solve it effortlessly.

So I'd say that I keep many tabs open for the exact opposite reason. It enhances what I can do, due to the limitations of my brain.

Within a few decades, I expect for the concept of open tabs and bookmarks to merge. We'll be keeping far more tabs open, and flipping between them effortlessly, or scrolling back to that snapshot in time effortlessly.

I imagine closing tabs will be being like closing Emacs buffers. In practice, you practically never have the need to close an Emacs buffer, for anything you might have a small chance of wanting to work on again soon.

There's a plugin for that (tm). I use unload tab quiet successfully. The only problems I had were with pdfjs tabs.

https://addons.mozilla.org/en-us/firefox/addon/unloadtab/

Compartments are not quite what I'm talking about.

I'm more talking about metadata / caches. There's a fair bit of stuff that can be global with a single process that cannot be with multiple processes. Sometimes you can use shared memory tricks, but not always.

Also: I wasn't aware there was that much of a memory penalty. Yow.

Yea the creator is asking for funding to port. He is just waiting for Mozilla to deliver which they said the were going to do.

the creator or noscript is working on it and from what i've read mozilla is aware of the issues and doing what they can from their end to make it possible for him to make it compatable: https://bugzilla.mozilla.org/show_bug.cgi?id=1058542

Yep, add-ons that connect background logic and "on-site" logic are going to have a lot of issues. Some APIs change from sync to async (which is good anyway). Some others are replaced or removed.

The two projects are independent; work on Electrolysis (multi-process Firefox) actually predates Servo. Old versions of mobile Firefox used Electrolysis, for example. But converting desktop Firefox and supporting its whole add-on ecosystem is a huge project, and was also put on hold for a long time.

Servo isn't aiming at replacing Gecko in Firefox, but it is aiming to be production-ready code. The plan is to make it embeddable like webkit. https://news.ycombinator.com/item?id=9541138

New multiprocess mode is a big pain for add-on developers. More details https://developer.mozilla.org/en-US/Add-ons/Working_with_mul...

I am not sure about the memory consumption, but since Chrome seems to have solved this topic, also Firefox should be able to, and maybe it's also time for me to switch back?

The reason I never promoted Chrome/ium to my "main" browser, instead using it sporadically whenever I decided I wanted to look at a page that use Flash is basically because Chrome is extremely RAM and CPU hungry in use cases where the number of user tabs are high (not sure what the tipping point is, but I regularly have more than 100 tabs present in my browser -- granted, not necessarily loaded).

Restoring a session with that many tabs basically disables the computer if using Chrome, necessitating a coffee break while pages load. Electrolysis in Firefox retains the lower RAM and CPU usage of the single process model, and also happens to feel much snappier day to day - I would absolutely recommend that you give the latest nightlies a shot -- or Firefox Aurora, which prompts users to turn it on: https://wiki.mozilla.org/Electrolysis#Schedule

I don't think they've solved it.

I also switched to Chromium a few years ago because it felt way more responsive at the time. Then slowly over time it grew into this beast using over 7GB of memory for my ~50 reasonable tabs (nothing extreme, mostly articles) and it started thrashing my system.

I've just recently switched back to Firefox and opened the exact same tabs: it's using 1.25GB. It feels a little slower at times but well within my requirements of usability. I refuse to waste all my memory for some text in a browser.

The nightly builds have to pass a suite of automated tests before they are published. They're not 100% stable but they're not crashy very often.

I've switched back to Firefox (initially because Chrome kept crashing after 1-2 hours on my machine). Now, I really like it, primarily because I can mess with userChrome.css. But I'm concerned that e10s will reintroduce the instability that caused me to leave Chrome (though I have no real evidence for this).

I often have hundreds and Chrome just dies when this happens (not to mention it eats tons of RAM -- they need their own MemShrink project). Firefox continues to work and uses far less RAM for the same set of pages.

You can do that in Chrome at least with blackboxing:

https://developer.chrome.com/devtools/docs/blackboxing

The Firefox debugger should automatically blackbox minified sources. You can also click on the little eye icon in the debugger panel to manually blackbox sources.

You can also use the developer toolbar to run a command like `dbg blackbox --glob *-min.js` etc. to blackbox a bunch of stuff at once.

https://developer.mozilla.org/en-US/docs/Tools/Debugger/How_...

This was what motivated me to switch to Chrome several years ago.

Reader view is also available in the Beta channel if you don't want to go as far as running nightlies just to get it. https://www.mozilla.org/en-US/firefox/channel/#beta

Yea I am with you, I love Chrome and I love that its basically my little mini xplat OS. That of course comes with a price of being a battery hog, if you don't want to use all the benefits Google is cramming into their browser, then I can see the allure of FF. I imagine that represents a fair number of FireFox's users as well. I imagine they won't abandon you friend. :)

Hypothetically, 50 processes all running separate unsynchronized wakeup timers and event loops could bring the processor out of sleep 50x more often than a single process.

I assume all graphics data is sent from the tab sub-processes to the main process (Chrome and similar in IE9-11). Multiprocess is different in Firefox, to get full multiprocess (per tab) we maybe have to wait a bit longer, for a Servo based browser.

Launching processes is a bit expensive especially on WinNT series (up to Win10), but ultimately it's the way to go ("sandbox" = sub-processes with minimum permissions) - even Servo with its Rust language use it as certain parts like the JavaScript engine are still C/C++ based (come from Firefox/gecko) for the near future and can crash.

Do you have data on Firefox using less battery? I thought the order for energy usage was Safari < Chrome < Firefox (but can't find anything to back that up either).

It is a bit of a memory hog as well, but yes, it's battery life is just fantastic.

Windows and Linux should be able to do that, too [1] - any idea if Chrome or Firefox make use of it?

[1]: http://en.wikipedia.org/wiki/Timer_coalescing

They made some battery improvements on Windows, but it's still a huge battery hog on Mac.

Battery life on FireFox is good if you use "lazy tabs" feature. If you need more battery, you just restart the browser and it only loads the tabs you open, so the old ones won't have JS working.

FF on Windows (work) is rock solid for me, while on Mac (home) it becomes unusable (too slow) after a few days, and also is a memory hog. I do keep 100s of tabs open on both, although most of those are usually not loaded.

Thanks for the offer. But I believe that the decision to remove the Forward button when there is no 'Forward' history was a design decision. Unfortunately, it has the unpleasant effect of resizing the address bar as well. So as you click through tabs, or click links, the address bar keeps resiing depending on the state of the history in that tab.

These 'design' decisions are quite silly IMHO. But I will find the original bug report and CC you on it.

https://bugzilla.mozilla.org/show_bug.cgi?id=748291

Here is one of several you get when you search for 'Forward' button

Often you need to preserve some state that is lost when using bookmarks (e.g. scroll position, a confirmation message that will be lost on refresh, a paused game/video etc.)

I'm trying the builtin Tab Groups feature now.

For Chrome, there is this great extension called "Tabs Outliner". Gets work done really great! Pity that after so much time there is no FF equivalent...

With bookmarks you have to put additional time for organization and saving them. When I am researching something, I prefer just opening a bunch of tabs and they may stay open for quite a long time. When I am done, I close all of them. The main sites that I use daily, are usually bookmarked, yes.

I'm also a very heavy tab user but I refuse to call it a mental disorder. It is simply an aspect of a workflow among another dime dozen. Web page hoarding may be a disorder though, but in this case it'll be disorder regardless of you're piling them on tabs, bookmarks or Pocket.

It's like a super convenient temporary bookmark, without any of the hassle of bookmark management.

I currently have 80 tabs open, and process-per-tab is not something I'm looking forward to.

I run something similar with 4 workspaces. I solved the "browser crashes taking down everything" problem by setting up 4 different profiles in firefox. Create a batch script to fire up firefox in the right profile for the right workspace.

It's worked well for me, when flash inevitably crashes it doesn't take the other workspaces with it, but it's perhaps not the most elegant of solutions.

Wh-whoa . . . I think you just set some sort of a record over there.

Unless you specifically tweak the UI to enable really small tabs, which is among the first things I do on a fresh install. Favicon + a small number of pixels for padding, way way less than Google allows me to get away with! Slap on a bunch of tab groups and I'm set.

I'm quite comfortable with a tab group filled to the point where the tab bar only displays favicons, but hasn't gotten to the point where it lets me scroll yet. That way I can rely on spatial memory to get to the right tab, without necessarily seeing the title!

Of course, searching for the right tab is an option, just like you said. I love the fact that Firefox also activates the correct tab group automatically.

I use Tree Style Tab for this, although I hate the actual tree functionality - it just happens to be the only reasonable vertical tab solution I've found. Unfortunately, it seems to get a little bit laggy with more than a couple hundred tabs.

Once you get used to the tab groups they can be very powerful. I use them for contexts myself; one for casual browsing, one for development for client x, one for client y etc, one for research, and the list goes on.

Obviously you can easily achieve the same thing in separate windows as well, so ultimately I suppose it doesn't make a huge difference, but it's the way I find makes for the biggest difference in separating workspaces.

If you are interested in grouping the tabs, have a look at this addon:

https://addons.mozilla.org/en-US/firefox/addon/tree-style-ta...

It allows you to use your tab-list in a hierarchical way, sort of like a filesystem. I group things under obvious roots, and then collapse it till needed.

I said tab but I don't actually use the UI concept of a "tab", though I could by M-x tab-bar-mode, because you're right it doesn't scale very well to large numbers, in my experience

I use buffers (in Conkeror). Buffers are just tabs without the actual tab UI. So unless I'm switching buffers, the only visible UI difference between having one buffer and 2000 buffers is the string "[2011/2011]" in my status-line showing my current buffer number and total number of buffers.

I can press C-x b (switch-to-buffer, I bind to M-a) to show a filterable list of my current buffers (favicon, url, title). I can type part of the url or page title (even when tab is unloaded) to filter my buffer list before switching to one. I can also navigate tabs "spatially" (from tab #2 to either tab #1 or #3) or by recently used (bury/unbury-buffer or switch-to-recent-buffer which shows buffer list in most recently used order) or by domain (next-buffer-same-host) or by whether the buffer is playing audio (switch-to-audio-buffer).

Also, in the vast majority of cases I only access recent tabs near the end of the list. I can press 9 or 0 to go to my second-to-last or last buffer.

The favicon is ok. I close them when there is no space to display the favicon.

Ironically, Chrome on Android handles this better than Chrome on the desktop. I have 15 tabs open on desktop Chrome right now, and it's getting a bit cramped. My Note 4? 33.

I use the "Tree Style Tab" add-on

"Open Tab Count" works nicely for me.

Wow, I thought I was in the top "tabbers" with my 300 tabs or so (well, 300 at work and 300 at home), but I see I am far from that !

Nonetheless, that's why I like firefox, I can do that, not so possible with Chrome. So like other said, I really really hope that they take into account this use case.

I do use pocket. Some of these links will end up in pocket, when I get around to looking at them closer if I decide they are long and I want to read them on my mobile devices.

I use one called UnloadTab. Works a treat, and does exactly what it says on the box!

I use Session Manager [1] for this. It has a "restore tabs on demand" option. I usually end up restarting the browser every week or two, either due to Windows updates, Firefox updates, or getting enough active tabs that the browser crashes. When it reloads, I only have one loaded tab, and start the cycle over again.

I think the lazy loading on session restore has been built in to Firefox for a while now, but I still use Session Manager. It shows me the number of tabs in the session before I choose to restore it, and if I hit a problematic page that is making the browser immediately crash, I can remove that page from the session before restoring, as well.

[1]: https://addons.mozilla.org/En-us/firefox/addon/session-manag...

There's tabvention, automatic 'tab list' backup as bookmark folders if you reach a certain (configurable) number.

https://chrome.google.com/webstore/detail/tabvention/kcjmdpj...

I like being able to switch to any of my tabs using the exact same UI technique as I would for any other tab, and press qqqqqqqqqq to view and kill many of tabs in succession.

I used to do somethingng similar but I've been using reading lists and a little more self control to manage most of my favs now.

Yes, that's called "tabs". Especially now that tab content is not autoloaded and autorendered. The bookmark metaphor simply doesn't fit everyone's mental model; tabs work much better.

It depends on what you do. Doing research requires a lot of resources (tabs) especially if you do it in an non-linear way. Consuming a content requires only on tab.

I open and use dozens of tabs (up to 100, then I bookmark all with one click and close all). But all tabs are active in memory in IE11 or Chrome so I can switch between them (sure I trade GBs of RAM for time, but that's okay). Firefox unloads tabs, so it reloads the page - that's better if you re-open Firefox as it only loads one tab instead of loading all tabs like in Chrome/IE but worse if you have it open and actually work in the browser. So for me it's a trade off, and I find it good I have a choice for different tasks I can choose the best way.

Ever since the dialup era, when all we had was "open in new window", I would browse by reading down a page and opening interesting-looking links in new windows and letting them load while carrying on with the original page.

Tabs are a good LIFO stack of things which are currently "live", or at least not dealt with yet. It's easier to navigate than history or bookmarks. You could argue that at some point tabs should "spill" into bookmarks, but that requires making a decision.

I've seen it irregularly on multiple machines, Windows 7, Windows 8 and now Mac OS X. It's actually really soured me on the whole idea of a multi-process architecture. I understand the theoretical benefits, but I don't see messages that a particular tab crashed that much more often than that the entire browser crashed.

"Little free memory" means that Chrome has eaten all my ram though.

Chrome is really lagging behind Firefox in this, as it has no backgrounding / unloading process that I'm aware of to maintain a reasonable memory footprint.

It also attempts to render every tab at once when restoring after a crash - another obvious problem.

Let me guess, it's a process like Flash that kills all of your tabs?

That's why having proprietary technology in browsers sucks because you can't really implement it the way you want to (as a browser vendor).

Or maybe not, I think they have automated crash reporting (I even used their library, breakpad) but my Chrome has been very consistent in crashing on Windows wakeup for over a year now.

This summer I'm going to be working on an implementation of software based fault isolation for my masters degree. We are looking to sandbox a web server without the need to partition via processes and incur expensive interprocess communication and context switching. I don't see why it couldn't work for Firefox either.

Here is the original paper: https://crypto.stanford.edu/cs155/papers/sfi.pdf

All changes will disrupt someones workflow[1]. I suppose browsers are no exception.

1: https://xkcd.com/1172/

Bad according to who?

Six years in the making? Wow...

At this point pretty much all (modern) browsers except Firefox have this.

Wouldn't too many processes bloat memory? I hope it will be configurable to have some balance.

Please elaborate, because IIRC the whole reason for offloading flash to a separate process was letting it crash without affecting the main process, and it fulfilled its duty every the time I've experienced a Flash crash.

Tested it today and the performance improvement seems very significant. Good job Mozilla (wow, I haven't said that in a while...)

I hope this doesn't lead to the overhead seen in Chrome. The overhead is constant and all the time; the browser is far from crashing all the time. I'm honestly very skeptic about the tradeoff here. And with the move to HTML5 and away from binaries ran by a browser engine, I'm unsure about the necessity due to current security issues in modern browsers too. The security nightmares in browsers always seem to have been related to ActiveX, NPAPI, running black boxes in general.

I actually think this was a far better idea (but ironically unthought of) during the days of ActiveX and a much less sensible idea today in 2015.

Other browsers are multi-process too? hmmm...

I've been using Chrome since Paul Irish started working on the Dev Tools. I used to have crashes when i had 120 tabs, but with Flashblock and uBlock i've had none.