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Showing posts from February, 2023

Firefox 110 on POWER


Firefox 110 is out, with graphics performance improvements like GPU-accelerated 2D canvas and faster WebGL, and the usual under the hood updates. The record's still broken and bug 1775202 still is too, so you'll either need this patch — but this time without the line containing desktop_capture/desktop_capture_gn, since that's gone in the latest WebRTC update — or put --disable-webrtc in your .mozconfig if you don't need WebRTC at all. I also had to put #pragma GCC diagnostic ignored "-Wnonnull" into js/src/irregexp/imported/regexp-parser.cc for optimized builds to complete on this Fedora 37 system and I suspect this is a gcc bug; you may not need it if you're not using gcc 12.2.1 or build with clang. Finally, I trimmed yet another patch from the PGO-LTO diff, so use the new one for Firefox 110 and the .mozconfigs from Firefox 105.

Vikings now has Blackbirds


If you're on the other side of that great pond called the Atlantic, Vikings' OpenPOWER store now lists Blackbirds starting at €3695 + VAT. Not just the board, the package includes a "4-core DD2.3 (v2) CPU, 2U heatsink, 16GB ECC RAM, bequiet! TFX power supply, all packaged nicely in a Antec slim desktop case." That's already a nice quiet basic system and more than enough to get you started with OpenPOWER, but if you want something almost silent, consider pairing it with their so far exclusive water block assembly for POWER9 for €155 + VAT, though you'll need to BYO pump, tubing, reservoir and fluid.

Linux 6.2


Linux 6.2 is out. Among its marquee updates are improved Rust-in-kernel support (strings, formatting and printing, memory allocation, macros, etc.), adding TCP Protective Load Balancing (PLB) for IPv6, reducing the overhead of read-copy update (RCU) operations using lazy callbacks, performance and RAID improvements for Btrfs, and userspace support for runtime verification with safety-critical systems. And, of course, support for Apple silicon and Retbleed sucks less on Skylake, but who cares about that around here anyway?

On the Power ISA side, probably the most noteworthy change is official support for big endian ELFv2 kernels. A nice upgrade for our Sir Mix-A-Lot brigade! Another interesting commit is the one to allow compile time support for the lharx and lbarx instructions (present on ISA v2.06/POWER7 and up). The lwarx (32-bit word) and ldarx (64-bit doubleword) load instructions, along with the corresponding store instructions stwcx. and stdcx. (and a conditional branch), are used to implement atomic load-store-compare/exchange operations by placing and checking reservations on particular memory locations. The newer instructions can do this at halfword (short) and byte level respectively (with sthcx. and stbcx.) instead of reserving at least an entire 32-bit word, reducing contention in tightly packed structs. In the future, it might also benefit the newly introduced Power ISA-specific spinlock implementation as well, which is also new in this release.

Expect 6.2 to make it to bleeding edge users and Fedora in the very near future.