audidude

If you have a thinkpad, you can probably extract the XML configuration from the windows driver installer using innoextract for your laptop. Then you can map those to pipewire settings with wireplumber to get very similar output to windows which was tuned in labs by the manufacturer (minus dolby atmos/dax).

Here is one for a recent thinkpad p1 gen8, no app necessary.

https://github.com/chergert/thinkpad-p1-gen8-pipewire-config

This is true. I wrote a sandbox for applications shipped on an immutable distro last month and it uses all the same portals just fine but no ostree/flatpak whatsoever.

You also can have separate portals implemented with different processes if you, you know, use d-bus properly.

They are real for some. I have Aphantasia but my wife has Hyperphantasia so we compare notes often. Each of us are at the edge of the spectrum.

I didn't understand flashbacks in movies until about a decade ago when I realized I had it. What a corny and lazy story-telling-tool I'd tell myself.

Very much depends on what you look like.

I'm white, but my wife is not. The moment you step out of Portland the racism is palpable. And even in Portland you have a bunch of white people that try so hard to not be racist that they come off super awkward and weird.

It's a thing.

Not that France isn't, but it's different. Some white guy was cat-calling my wife the other day in Mandarin. She is not Chinese...

It's awesome. I moved to France from Portland, Oregon this year. I went from 1gb to 8gb fiber for half the cost in France.

This was something I would have never understood living in the US until I moved to France 4 months ago. And yeah, as much as I dislike the company, those lockers are clutch.

Does it still completely screw up file/group owners in user containers? Because they keep saying it gets fixed and then that 1 out of 10 times it's not.

> I found it hard to believe we couldn’t get a wakeup timer more granular than 1 ms, so I looked at what KWin was using. Indeed, it was passing the sleep duration in milliseconds to a QBasicTimer.

I fixed the same thing in GNOME a few years ago across GLib, GTK, and Mutter/GNOME Shell. It required getting glib onto ppoll() finally.

This feature (fibers in systemd) was also modeled after libdex (which I wrote for GNOME).

I've been doing this with something very similar in GNOME for years now. It also does io_uring, threadpool schedulers, workstealing, "pollable semaphores" (like IRIX), profiler integration, and makes fibers implemented as futures themselves.

https://github.com/GNOME/libdex/

The good news is that before writing Ptyxis, I also ported GNOME Terminal to GTK 4 and doubled the performance of VTE. So you know, use whatever you like.

Almost all of that is Mesa shaders and GTK's CPU side font-cache for GL/Vulkan, compiled CSS state, FWIW.

If you run:

GSK_RENDERER=cairo ptyxis -s

You can verify that with 69,985 here RES and 52,428 of that SHR. With 5 tabs open it jumped to 71,208 here. Presumably for the encrypted scrollback pre-allocations.

You still may not choose to use it, but it should stay relatively similar the more tabs you open.

Also, it's not a core GNOME app. It's just an app I wrote for me that the distros seem to have liked for its design/platform integration.

In most cases you're already using signalfd in places where libdex runs.

> I'm not normally keen to "well actually" people with the C standard, but .. if you're writing in assembly, you're not writing in C.

These days on Linux/BSD/Solaris/macOS you can use makecontext()/swapcontext() from ucontext.h and it will turn out roughly the same performance on important architectures as what everyone used to do with custom assembly. And you already have fiber functions as part of the Windows API to trampoline.

I had to support a number of architectures in libdex for Debian. This is GNOME code of course, which isn't everyone's cup of C. (It also supports BSDs/Linux/macOS/Solaris/Windows).

* https://packages.debian.org/sid/libdex-1-1

* https://gitlab.gnome.org/GNOME/libdex

In X11 we kept things simple by offering:

* Core protocol drawing (lines, rectangles, arcs, the classics)

* XRender for compositing and alpha

* XShm for shared-memory blits

* GLX if you felt like bringing a GPU to a 2D fight

* XVideo for overlay video paths

* Pixmaps vs Windows, because why have one drawable when you can have two subtly different ones

* And of course, indirect rendering over the network if you enjoy latency as a design constraint

So the state of 2025 then tests a VTE that is from 2023? 4 major releases behind? And through a GTK 3 app, not even a GTK 4 one which will use the GPU?

Red Hat announced RISC-V yesterday with RHEL 10. So this seems rather expected.

https://www.redhat.com/en/blog/red-hat-partners-with-sifive-...

As someone who went down this path many years ago, I think the GTK numbers in the article are a bit misleading. You wouldn't create 1000 buttons to do a flamegraph properly in GTK.

In Sysprof, it uses a single widget for the flamegraph which means in less than 150 mb resident I can browse recordings in the GB size range. It really comes down to how much data gets symbolized at load time as the captures themselves are mmap'able. In nominal cases, Sysprof even calculates those and appends them after the capture phase stops so they can be mmap'd too.

That just leaves the augmented n-ary tree key'd by instruction pointer converted to string key, which naturally deduplicates/compresses.

The biggest chunk of memory consumed is GPU shaders.

https://pagure.io/fesco/issue/2817#comment-826636 will probably get you started into the relevant paths. Python 3.12 was going to include frame-pointers anyway for perf to boot. So they needed to fix this regardless.

This is a bit of a mischaracterization of the Python side of things.

They only opted out for 3.11 which did not yet have the perf-integration fixes anyway. 3.12 uses frame-pointers just fine.

I think your viewpoint is valid.

My experience is on performance tuning the other side you mention. Cross-application, cross-library, whole-system, daemons, etc. Basically, "the whole OS as it's shipped to users".

For my case, I need the whole system setup correctly before it even starts to be useful. For your case, you only need the specific library or application compiled correctly. The rest of the system is negligible and probably not even used. Who would optimize SIMD routines next to function calls anyway?

It's a disaster no doubt.

But, at least from the GNOME side of things, we've been complaining about it for roughly 15 years and kept getting push-back in the form of "we'll make something better".

Now that we have frame-pointers enabled in Fedora, Ubuntu, Arch, etc we're starting to see movement on realistic alternatives. So in many ways, I think the moral hazard was waiting until 2023 to enable them.

Absolutely. We've gotten numerous double digit performance improvements across applications, libraries, and system daemons because of frame-pointers in Fedora (and that's just from me).

I regularly have users run Sysprof and upload it to issues. It's immensely powerful to be able to see what is going on systems which are having issues. I'd argue it's one of the major reasons GNOME performance has gotten so much better in the recent-past.

You can't do that when step one is reinstall another distro and reproduce your problem.

Additionally, the overhead for performance related things that could fall into the 1% range (hint, it's not much) rarely are using the system libraries in such a way anyway that would cause this. They can compile that app with frame-pointers disabled. And for stuff where they do use system libraries (qsort, bsearch, strlen, etc) the frame pointer is negligible to the work being performed. You're margin of error is way larger than the theoretical overhead.

> Shadow stacks are cool but aren't they limited to a fixed number of entries?

Current available hardware yes. But I think some of the future Intel stuff was going to allow for much larger depth.

> Is the memory overhead of lookup tables for very large programs acceptable?

I don't think SFrame is as "dense" as DWARF as a format so you trade a bit of memory size for a much faster unwind experience. But you are definitely right that this adds memory pressure that could otherwise be ignored.

Especially if the anomalies are what they sound like, just account for them statistically. You get a PID for cost accounting in the perf_event frame anyway.

It does cause more memory pressure because the kernel will have to look at the user-space memory for decoding registers.

So yes it will be faster than alternatives to frame-pointers, but it still wont be as fast as frame pointers.

I added support to Sysprof this weekend for unwinding using libdwfl and DWARF/CFI/eh_frame/etc techniques that Serhei did in eu-stacktrace.

The overhead is about 10% of samples. But at least you can unwind on systems without frame-pointers. Personally I'll take the statistical anomalies of frame-pointers which still allow you to know what PID/TID are your cost center even if you don't get perfect unwinds. Everyone seems motivated towards SFrame going forward, which is good.

https://blogs.gnome.org/chergert/2024/11/03/profiling-w-o-fr...

These are two common things I ask new friends so that I can communicate better with them (aphantasia and inner monologue).

Nothing, I have aphantasia.