Fedora 39

Fedora 39 is out, the Linux distro I use personally on my Talos II and Blackbird systems. Since I'm doing a lot of remote work with the new $DAYJOB it might be a bit before I can sit down with it but there will be the usual mini-review (here's what I had to say about Fedora 38). This release is based on kernel 6.5 and GNOME 45, with LLVM 17, Perl 5.38, glibc 2.38 and gcc 13.2. As usual, Fedora 37 will EOL one month after this release.

However, F39 isn't really the big news, and probably won't be a very exciting (or bumpy) release. Instead, the bigger and possibly more obnoxious change will occur with Fedora 40 when the Plasma spin (which I use instead of GNOME) is expected to completely drop X11 support, and the same is likely coming for GNOME 46 which will occur in the same version. It will be interesting, to say the least, to see how this affects people running OpenPOWER systems without GPUs to be completely blob-less. I've not been terribly happy with Wayland on the Blackbird's ASpeed BMC framebuffer and I haven't seen anything to indicate that its deficiencies have improved. Wonder how well it would work on the X1 ...

Firefox 119 and the next ppc64le JITeration

Although I've been a bit preoccupied lately with a new $DAYJOB which has required me to be remote, let's not bury the (larger) lede: the first iteration of the Firefox/SpiderMonkey ppc64le JIT is being evaluated by Mozilla to determine if the changes are acceptable. Please don't spam the Bugzilla entry with drive-by comments, but if you'd like to observe its progress, you can follow along in bug 1860412.

That doesn't mean, of course, that you can't try it yourself. The current JIT state for 115ESR now supports baseline Wasm as well as full optimizing Ion compilation for regular JS, and passes the complete test suite on Linux. It does not yet support POWER8, nor the optimizing Wasm compiler, so some applications will not run as well as they should (and obnoxiously asm.js code is not JITted at all in this configuration because it relies on the optimizing Wasm compiler, despite the fact it's regular JavaScript — for TenFourFox, which didn't support Wasm otherwise, I hacked JavaScript to simply compile asm.js with regular Ion). However, I do intend to add support for optimized Wasm and later POWER8, and with that said, the testers I've been seeding this with see good improvements for the vast majority of sites and no additional reproducible crashes so far.

If you'd like to give it a shot as well, then apply the new patches numerically and build as we did for Firefox 115, using the .mozconfigs from Firefox 105. For your convenience the JIT patch set already includes the PGO-LTO and WebRTC fixes for that version. If you don't want to roll your own browser (though I highly recommend it), then Dan Horák has you covered with a copr build for Fedora users. However, I don't intend to backport POWER8 or optimizing Wasm support to 115ESR; future work will be done on trunk, assuming Mozilla is fine with the existing changes. Do not post bugs with the ESR JIT to bug 1860412.

Apart from that, the other Firefox news is anticlimatic: Firefox 119 (I did a test build of Fx118 but hadn't tested enough to post about it) builds fine with the WebRTC patch from Fx116 (or --disable-webrtc in your .mozconfig), the PGO-LTO patch from Fx117 and the .mozconfigs from Firefox 105.