On Fri, Nov 22, 2024 at 9:44 AM Michel Lind <michel@michel-slm.name> wrote:
cc:ing Andrii Nakryiko here, one of our resident profiling gurus at Meta, to bring him into the conversation. Apologies for yet another subthread, but there are different questions from Aaron and Jiry and since Andrii is not subscribed to the lists this is the only way to keep both packaging and factory lists in sync.
Thanks Michel! It turned out I can reply through website UI (which I did on three separate replies), but thanks for looping me in! TL;DR, I'm very supportive of enabling frame pointers. There is no practical alternative to them right now. Maybe in a few years (and I'm one of the people who are working towards SFrame becoming one of those alternatives), but definitely not in the next year or two (if not more). We went through a lot (and I mean A LOT) of frame pointer discussion with Fedora proposal, I'm not sure I see the value to do that all over again. It's been proven useful and no significant regression was reported (as far as I'm aware). In big production (at Meta), there is no way we are going back to disabling frame pointers, it's been that useful and powers tons of efficiency work for many people in the company. I hope openSUSE community will follow an example of Fedora and Ubuntu and will make entire software ecosystem much more amenable to profiling and optimization work. Even if most users are not the immediate *users of this*, they get all the benefits of optimization work this change enables for tons of other developers.
Cheers,
-- Michel
On Sat, Nov 16, 2024 at 01:24:05PM -0500, Neal Gompa wrote:
Hello,
I would like to change openSUSE's default build flags in rpm and rpm-config-SUSE to incorporate frame pointers (and equivalents on other architectures) to support real-time profiling and observability on SUSE distributions.
In practice, this would mean essentially adopting the same tunables that exist in Fedora[1] for openSUSE to turn them on by default and to allow packages or OBS projects to selectively opt out as needed.
The reasons to do so are threefold:
* It is a major competitive disadvantage for us to lack the ability to do cheap real-time profiling and observability. Fedora[2], Ubuntu[3], Arch Linux[4], and AlmaLinux[5] all now do this, and thus support this capability. * The performance hit for having it vs not is insignitifcant[6]. * There are new tools in both the cloud-native and regular systems development worlds that leverage this, and openSUSE should be an enabler of those technologies.
I want openSUSE to be a great place for people to develop and optimize workloads on, especially desktop ones, where most of the tooling we have for tracing and profiling is broken without frame pointers (see Sysprof and Hotspot from GNOME and KDE respectively, which both rely on frame pointers to have cheap real-time tracing for performance analysis). And given that we advertise as the "makers' choice", I think it would definitely be on-brand for us to have the capability to better support makers and shakers.
For those interested in more detail about frame pointers, Brendan Gregg has a decent post about it[7]. I have also submitted a parallel request for openSUSE Leap 16 to have this feature enabled too[8].
I truly believe this would give us an even better footing with the broader community of developers and operators and make SUSE distributions very attractive for FOSS and proprietary software alike.
Best regards, Neal
[1]: https://src.fedoraproject.org/rpms/redhat-rpm-config/blob/93063bb396395b9a20... [2]: https://fedoraproject.org/wiki/Changes/fno-omit-frame-pointer [3]: https://ubuntu.com/blog/ubuntu-performance-engineering-with-frame-pointers-b... [4]: https://gitlab.archlinux.org/archlinux/rfcs/-/blob/master/rfcs/0026-fno-omit... [5]: https://almalinux.org/blog/2024-10-22-introducing-almalinux-os-kitten/ [6]: https://www.phoronix.com/review/fedora-38-beta-benchmarks [7]: https://www.brendangregg.com/blog/2024-03-17/the-return-of-the-frame-pointer... [8]: https://code.opensuse.org/leap/features/issue/175
-- 真実はいつも一つ！/ Always, there's only one truth!
-- _o) Michel Lind _( ) identities: https://keyoxide.org/5dce2e7e9c3b1cffd335c1d78b229d2f7ccc04f2