rapidhash

LuaJIT bindings to the reference rapidhash

Usage

lde add rapidhash

local rapidhash = require("rapidhash")

rapidhash.hash("hello")              --> uint64 cdata
rapidhash.hash("hello", 42)          --> number seeds accepted
rapidhash.hash("hello", 0x2aULL)     --> cdata seeds accepted
rapidhash.hex("hello")               --> "2f4e5e5b9b8b8b8b" hex string

Why not write it in LuaJIT?

LuaJIT does not support 128 bit integers natively. So performance is limited compared to a C implementation.

Speed

Measured with benchmarks/ on this machine (zero-copy FFI calls into the native core):

input	rapidhash	fnv1a (Lua baseline)
1 KB	~28 GB/s	~0.25 GB/s
lockfile (~15 KB)	~32 GB/s	~0.24 GB/s
64 KB	~31 GB/s	~0.24 GB/s
1 MB	~27 GB/s	—

~100× faster than the byte-at-a-time FNV-1a.