v0.2.0 (Feb 24, 2022)

What's Changed

Seeded CircleHash64 reached 10GB/s at less than 64-byte inputs and 15GB/s at 256-byte inputs.

• Optimize CircleHash64 without using assembly language by @fxamacker in #8
• Update ci-go-cover.yml and add CircleHash128 to TODOs by @fxamacker in #9

Full Changelog: v0.1.0...v0.2.0

What is CircleHash?

CircleHash is a family of non-cryptographic hash functions. CircleHash64 uses the fractional digits of π as default constants (nothing up my sleeve). CircleHash64 is fast, simple, and easy to audit/maintain.

CircleHash64 uses CircleHash64f by default, which is based on Google's Abseil C++ library internal hash.

	CircleHash64	Abseil C++	SipHash-2-4	xxh64
SAC worst-bit 0-128 byte inputs (lower % is better)	0.791% 🥇 w/ 99 bytes	0.862% w/ 67 bytes	0.852% w/ 125 bytes	0.832% w/ 113 bytes

☝️ Using demerphq/smhasher updated to test all input sizes 0-128 bytes (SAC test will take hours longer to run).

CircleHash64 is very fast at hashing short inputs with a 64-bit seed.

	CircleHash64 (seeded)	XXH3 (seeded)	XXH64 (w/o seed)	SipHash (seeded)
4 bytes	1.34 GB/s	1.21 GB/s	0.877 GB/s	0.361 GB/s
8 bytes	2.70 GB/s	2.41 GB/s	1.68 GB/s	0.642 GB/s
16 bytes	5.48 GB/s	5.21 GB/s	2.94 GB/s	1.03 GB/s
32 bytes	8.01 GB/s	7.08 GB/s	3.33 GB/s	1.46 GB/s
64 bytes	10.3 GB/s	9.33 GB/s	5.47 GB/s	1.83 GB/s
128 bytes	12.8 GB/s	11.6 GB/s	8.22 GB/s	2.09 GB/s
192 bytes	14.2 GB/s	9.86 GB/s	9.71 GB/s	2.17 GB/s
256 bytes	15.0 GB/s	8.19 GB/s	10.2 GB/s	2.22 GB/s

• Using Go 1.17.7, darwin_amd64, i7-1068NG7 CPU.
• Results from go test -bench=. -count=20 and benchstat
• Fastest XXH64 (written in Go+Assembly) doesn't support seed.

CircleHash64 was created when I needed a very fast hash for input sizes typically <= 128 bytes.

ℹ️ Non-cryptographic hashes should only be used in software designed to properly handle hash collisions. If you require a secure hash, please use a cryptographic hash (like the ones in SHA-3 standard).