WyHash 1.0.2
See the version list below for details.
dotnet add package WyHash --version 1.0.2
NuGet\Install-Package WyHash -Version 1.0.2
<PackageReference Include="WyHash" Version="1.0.2" />
paket add WyHash --version 1.0.2
#r "nuget: WyHash, 1.0.2"
// Install WyHash as a Cake Addin #addin nuget:?package=WyHash&version=1.0.2 // Install WyHash as a Cake Tool #tool nuget:?package=WyHash&version=1.0.2
wyhash-dotnet
Zero-allocation C# implementation of Wang Yi's 64-bit wyhash hash algorithm and wyrand PRNG.
wyhash is an extremely fast, portable hashing algorithm, and passes all of the SMHasher tests (which evaluates collision, dispersion and randomness qualities of hash functions).
Getting Started
Install the WyHash package from NuGet:
Install-Package WyHash
WyHash implements HashAlgorithm, so can be integrated into existing projects easily:
var seed = 42;
var hasher = WyHash64.Create(seed);
var result = hasher.ComputeHash(myData);
A common use case is getting the resulting hash as a 64-bit unsigned integer (ulong
), so a static convenience method is also provided:
// Note that if no seed is specified, it default to 0
var seed = 42;
var result = WyHash64.ComputeHash64(myData, seed);
The wyrand PRNG is also implemented:
var rng = new WyRng(42);
// Generate pseudorandom values
ulong a64BitVal = rng.NextLong();
uint a32BitVal = rng.Next();
// Fill a buffer with pseudorandom bytes
var buffer = new byte[256];
rng.NextBytes(buffer);
// Span is also supported
Span<byte> spanBuffer = stackalloc byte[128];
rng.NextBytes(spanBuffer);
Performance & Future Work
At present (May 2019), wyhash is the fastest algorithm in the SMHasher benchmark.
On a dev laptop with 64GB RAM and an Intel Xeon CPU E3-1545M v5 2.90GHz CPU, this implementation can process data at a rate of around 5.5GB/s on .NET Core 3, or 3.3GB/s on .NET Core 2 or the .NET Framework - this is very fast.
The reason for the performance improvement on .NET Core 3 is that it supports hardware intrinsics, and wyhash-dotnet uses the BMI2 MULX
instruction to achieve faster 64-bit integer multiplication (on systems where BMI2 is available). Support for intrinsics won't make it into the .NET Framework, but will also be in the newly announced .NET 5.
Note that PInvoke
ing into a native DLL built using the reference C code (see the WyHash.Native
project) achieves around 10.8GB/s (more or less RAM SPEED), so there is still work to do to bridge the performance gap between C# and native - I'm very much open to suggestions here!
Latest benchmarks (DataSize
is the size of data hashed, in bytes):
BenchmarkDotNet=v0.11.5, OS=Windows 7 SP1 (6.1.7601.0)
Intel Xeon CPU E3-1545M v5 2.90GHz, 1 CPU, 8 logical and 4 physical cores
Frequency=2836064 Hz, Resolution=352.6014 ns, Timer=TSC
.NET Core SDK=3.0.100-preview4-011223
[Host] : .NET Core 3.0.0-preview4-27615-11 (CoreCLR 4.6.27615.73, CoreFX 4.700.19.21213), 64bit RyuJIT
Core : .NET Core 3.0.0-preview4-27615-11 (CoreCLR 4.6.27615.73, CoreFX 4.700.19.21213), 64bit RyuJIT
Job=Core Runtime=Core
Method | DataSize | Mean | Error | StdDev | Min | Max | Ratio | RatioSD | Rank | Gen 0 | Gen 1 | Gen 2 | Allocated |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
TestXxHash | 100 | 20.84 ns | 0.4168 ns | 0.6964 ns | 20.02 ns | 22.99 ns | 0.95 | 0.03 | 2 | - | - | - | - |
TestXxHashNative | 100 | 24.33 ns | 0.3217 ns | 0.3009 ns | 23.99 ns | 24.92 ns | 1.10 | 0.02 | 4 | - | - | - | - |
TestWyHashNative | 100 | 18.63 ns | 0.1110 ns | 0.0984 ns | 18.47 ns | 18.87 ns | 0.84 | 0.01 | 1 | - | - | - | - |
TestWyHash | 100 | 22.18 ns | 0.2429 ns | 0.2273 ns | 21.84 ns | 22.52 ns | 1.00 | 0.00 | 3 | - | - | - | - |
TestXxHash | 1024 | 106.06 ns | 1.0322 ns | 0.9150 ns | 105.25 ns | 108.04 ns | 0.79 | 0.01 | 3 | - | - | - | - |
TestXxHashNative | 1024 | 93.75 ns | 1.9055 ns | 2.1943 ns | 91.79 ns | 99.02 ns | 0.71 | 0.02 | 2 | - | - | - | - |
TestWyHashNative | 1024 | 75.38 ns | 1.1722 ns | 0.9788 ns | 74.37 ns | 77.46 ns | 0.56 | 0.01 | 1 | - | - | - | - |
TestWyHash | 1024 | 133.58 ns | 2.0582 ns | 1.9252 ns | 131.38 ns | 137.66 ns | 1.00 | 0.00 | 4 | - | - | - | - |
Product | Versions Compatible and additional computed target framework versions. |
---|---|
.NET | net5.0 was computed. net5.0-windows was computed. net6.0 was computed. net6.0-android was computed. net6.0-ios was computed. net6.0-maccatalyst was computed. net6.0-macos was computed. net6.0-tvos was computed. net6.0-windows was computed. net7.0 was computed. net7.0-android was computed. net7.0-ios was computed. net7.0-maccatalyst was computed. net7.0-macos was computed. net7.0-tvos was computed. net7.0-windows was computed. net8.0 was computed. net8.0-android was computed. net8.0-browser was computed. net8.0-ios was computed. net8.0-maccatalyst was computed. net8.0-macos was computed. net8.0-tvos was computed. net8.0-windows was computed. |
.NET Core | netcoreapp2.0 was computed. netcoreapp2.1 was computed. netcoreapp2.2 was computed. netcoreapp3.0 is compatible. netcoreapp3.1 was computed. |
.NET Standard | netstandard2.0 is compatible. netstandard2.1 was computed. |
.NET Framework | net461 was computed. net462 is compatible. net463 was computed. net47 was computed. net471 was computed. net472 was computed. net48 was computed. net481 was computed. |
MonoAndroid | monoandroid was computed. |
MonoMac | monomac was computed. |
MonoTouch | monotouch was computed. |
Tizen | tizen40 was computed. tizen60 was computed. |
Xamarin.iOS | xamarinios was computed. |
Xamarin.Mac | xamarinmac was computed. |
Xamarin.TVOS | xamarintvos was computed. |
Xamarin.WatchOS | xamarinwatchos was computed. |
-
.NETCoreApp 3.0
- System.Memory (>= 4.5.2)
-
.NETFramework 4.6.2
- System.Memory (>= 4.5.2)
-
.NETStandard 2.0
- System.Memory (>= 4.5.2)
NuGet packages (3)
Showing the top 3 NuGet packages that depend on WyHash:
Package | Downloads |
---|---|
HQ
This package contains the full-stack build for HQ.io. |
|
TypeKitchen.Reflection
TypeKitchen is a small library for fast meta-programming in .NET. |
|
TypeKitchen.Differencing
TypeKitchen is a small library for fast meta-programming in .NET. |
GitHub repositories
This package is not used by any popular GitHub repositories.