Viewing profile — gsvelto

You're assuming that Firefox is eating all your commit space, but it's not, far from it, I can see it from the crash reports. You've got other applications running and they are als…

From the looks of it you have a minuscule page file (16MiB), that's why you're running out of commit space. I suggest setting it to auto-resize (the Windows default) which should p…

Could you open a bug on our tracker, and point to those crash reports? I'm very interested in analyzing real-world scenarios where this happens to figure out where those committed …

Yes it does, we've disabled tab unloading on Linux because low-memory detection just didn't work. We will re-enabled it sometimes down the line but only to avoid swap, not crashes.…

But is it? I wanted it to be tongue-in-cheek but the title is actually a rather accurate description of the contents of the article. This is a ~20 lines weird hack that we threw at…

Here's the thing: they're not! The reason those users where crashing was because something, somewhere (possibly in the graphics stack) was reserving ton of space without using it. …

I'm glad you noticed! We did indeed roll an improvement on Linux too, see: https://bugzilla.mozilla.org/show_bug.cgi?id=1771712 In a nutshell we're directing the OOM killer towards…

They do and so does jemalloc in Firefox, however that lowers contention, it doesn't let you do away with synchronization. Consider this simple scenario: a thread allocates a chunk …

You're confusing general purpose locks with special-purpose ones used in the memory allocator. Firefox has its own GP locks, you can find them here: https://searchfox.org/mozilla-c…

No specific hardware support is needed to implement a lock. The atomic operations are all accessible from user-space - they are platform dependent though. The problem with locks is…

In a word: no. Efficient locks can only be implemented with significant involvement from the kernel. The best locks that can be implemented entirely in user-space will still suffer…

If you could grab a profile of the problem with the Firefox profiler and file a bug it would be greatly appreciated. From the sounds of it it's probably an edge-case we're not awar…

Post author here, `__ulock_wait2` is used under the hood by `os_unfair_lock()`. I considered it but it would have required more scaffolding, especially to support all the versions …

Recent Linux kernels allow you to measure memory consumption from a QoS point-of-view via pressure stall information: https://www.kernel.org/doc/html/latest/accounting/psi.html Thi…

Unfortunately those crashes do not appear to be related to low memory scenarios. They seem to be genuine bugs in the screen reader. I think the right bug tracking them is this one:…

Detecting low memory scenarios is surprisingly hard on desktop operating systems, but trivially simple on Android/iOS. Firefox for Android already made extensive use of this featur…

Arch already uploads symbols for their Firefox builds so that's OK, it's the dependencies that are missing. Unwinding information is used to produce accurate stacks. If it's lackin…

Only public symbols and unwinding information is extracted from Arch packages because they don't have debuginfo like other distros. It's better than nothing.

That's a really tough problem to solve on Linux. We're actively working on it in order to make Firefox better behaved when memory gets tight but it's not easy. You can follow the w…

Yes, that's one of the benefits. Firefox has a very large user-base compared to other FOSS projects so we will often spot bugs that others haven't noticed simply thanks to the shee…

You're very welcome! If you're interested in the topic we've got a working group [1] and a very active channel on chat.mozilla.org [2]. Besides the actual stability work we've also…

I think I started scraping symbols from Fedora 34 builds on Monday, we probably haven't looked at those crashes yet.

We do gather symbol information on Windows too, but it's a lot less detailed than what we get from Linux. It also requires jumping through a lot of hoops. For example we get minima…

It's rasdaemon these days: https://www.setphaserstostun.org/posts/monitoring-ecc-memory...