quadsort
highway
quadsort | highway | |
---|---|---|
9 | 66 | |
2,106 | 3,656 | |
- | 2.1% | |
4.6 | 9.8 | |
6 months ago | about 17 hours ago | |
C | C++ | |
The Unlicense | Apache License 2.0 |
Stars - the number of stars that a project has on GitHub. Growth - month over month growth in stars.
Activity is a relative number indicating how actively a project is being developed. Recent commits have higher weight than older ones.
For example, an activity of 9.0 indicates that a project is amongst the top 10% of the most actively developed projects that we are tracking.
quadsort
-
10~17x faster than what? A performance analysis of Intel x86-SIMD-sort (AVX-512)
https://github.com/scandum/quadsort/blob/f171a0b26cf6bd6f6dc...
As you can see, quadsort 1.1.4.1 used 2 instead of 4 writes in the bi-directional parity merges. This was in June 2021, and would have compiled as branchless with clang, but as branched with gcc.
When I added a compile time check to use ternary operations for clang I was not adapting your work. I was well aware that clang compiled ternary operations as branchless, but I wasn't aware that rust did as well. I added the compile time check to use ternary operations for a fair performance comparison against glidesort.
https://raw.githubusercontent.com/scandum/fluxsort/main/imag...
As for ipnsort's small sort, it is very similar to quadsort's small sort, which uses stable sorting networks, instead of unstable sorting networks. From my perspective it's not exactly novel. I didn't go for unstable sorting networks in crumsort to increase code reuse, and to not reduce adaptivity.
-
Show HN: QuadSort, Esoteric Fast Sort
In the code it looks like the seed to the benchmark can be provided as the 4th command line argument: https://github.com/scandum/quadsort/blob/master/src/bench.c#...
-
When does big-oh notation become not helpful when comparing algorithms?
If you look at sorting for example, it's been proven that you can't do a comparison-based sort faster than O(n logn). You may then think that we've already found the fastest possible sorting algorithms since Quicksort and Mergesort are already O(n logn). However, new sorting algorithms keep being invented, for example Quadsort. They're all still O(n logn), but they do offer a considerable speed improvement over more traditional algorithms
- quadsort 1.1.5.1: Up to 2.5x faster than qsort() on random data
- Quadsort 1.1.5.1: Introducing cost effective branchless merging
- I tried creating a sorting algorithm in C language.
highway
-
Llamafile 0.7 Brings AVX-512 Support: 10x Faster Prompt Eval Times for AMD Zen 4
The bf16 dot instruction replaces 6 instructions: https://github.com/google/highway/blob/master/hwy/ops/x86_12...
-
JPEG XL and the Pareto Front
[0] for those interested in Highway.
It's also mentioned in [1], which starts off
> Today we're sharing open source code that can sort arrays of numbers about ten times as fast as the C++ std::sort, and outperforms state of the art architecture-specific algorithms, while being portable across all modern CPU architectures. Below we discuss how we achieved this.
[0] https://github.com/google/highway
[1] https://opensource.googleblog.com/2022/06/Vectorized%20and%2..., which has an associated paper at https://arxiv.org/pdf/2205.05982.pdf.
-
Gemma.cpp: lightweight, standalone C++ inference engine for Gemma models
Thanks so much!
Everyone working on this self-selected into contributing, so I think of it less as my team than ... a team?
Specifically want to call out: Jan Wassenberg (author of https://github.com/google/highway) and I started gemma.cpp as a small project just a few months ago + Phil Culliton, Dan Zheng, and Paul Chang + of course the GDM Gemma team.
-
From slow to SIMD: A Go optimization story
C++ users can enjoy Highway [1].
[1] https://github.com/google/highway/
- GDlog: A GPU-Accelerated Deductive Engine
-
Designing a SIMD Algorithm from Scratch
At that point it is better to have some kind of DSL that should not be in the main language, because it would target a much lower level than a typical program. The best effort I've seen in this scene was Google's Highway [1] (not to be confused with HighwayHash) and I even once attempted to recreate it in Rust, but it is still distanced from my ideal.
[1] https://github.com/google/highway
-
SIMD Everywhere Optimization from ARM Neon to RISC-V Vector Extensions
Interesting, thanks for sharing :)
At the time we open-sourced Highway, the standardization process had already started and there were some discussions.
I'm curious why stdlib is the only path you see to default? Compare the activity level of https://github.com/VcDevel/std-simd vs https://github.com/google/highway. As to open-source usage, after years of std::experimental, I see <200 search hits [1], vs >400 for Highway [2], even after excluding several library users.
But that aside, I'm not convinced standardization is the best path for a SIMD library. We and external users extend Highway on a weekly basis as new use cases arise. What if we deferred those changes to 3-monthly meetings, or had to wait for one meeting per WD, CD, (FCD), DIS, (FDIS) stage before it's standardized? Standardization seems more useful for rarely-changing things.
1: https://sourcegraph.com/search?q=context:global+std::experim...
2: https://sourcegraph.com/search?q=context:global+HWY_NAMESPAC...
-
Permuting Bits with GF2P8AFFINEQB
Thanks for the link. We were previously using GFNI for bit reversal and 8-bit shifts, and I just extended that to our 8-bit BroadcastSignBit (https://github.com/google/highway/pull/1784).
-
Six times faster than C
You could study Google's Highway library [1].
[1] https://github.com/google/highway
-
AMD EPYC 97x4 “Bergamo” CPUs: 128 Zen 4c CPU Cores for Servers, Shipping Now
Runtime feature detection need not be rare nor hard, it's a few dozen lines of boilerplate. You can even write your code just once: see https://github.com/google/highway#examples.
What are some alternatives?
pdqsort - Pattern-defeating quicksort.
xsimd - C++ wrappers for SIMD intrinsics and parallelized, optimized mathematical functions (SSE, AVX, AVX512, NEON, SVE))
fluxsort - A fast branchless stable quicksort / mergesort hybrid that is highly adaptive.
Vc - SIMD Vector Classes for C++
blitsort - Blitsort is an in-place stable adaptive rotate mergesort / quicksort.
swup - Versatile and extensible page transition library for server-rendered websites 🎉
Klib - A standalone and lightweight C library
DirectXMath - DirectXMath is an all inline SIMD C++ linear algebra library for use in games and graphics apps
sort-test - A simple sort benchmarking tool
riscv-v-spec - Working draft of the proposed RISC-V V vector extension
rotate - A collection of array rotation algorithms.
jpeg-xl