Generates CRC hashes for strings - for use by node redis clients to determine key slots.

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1821.1.22 years ago8 years agoMinified + gzip package size for cluster-key-slot in KB


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Redis Key Slot Calculator
A high performance redis cluster key slot calculator for node redis clients e.g. noderedis, ioredis and redis-clustr.
This also handles key tags such as somekey{actualTag}.


Install with NPM:
npm install cluster-key-slot --save


const calculateSlot = require('cluster-key-slot');
const calculateMultipleSlots = require('cluster-key-slot').generateMulti;

// ...

// a single slot number
const slot = calculateSlot('test:key:{butOnlyThis}redis');
// Buffer is also supported
const anotherSlot = calculateSlot(Buffer.from([0x7b, 0x7d, 0x2a]));

// multiple keys - multi returns a single key slot number, returns -1 if any
// of the keys does not match the base slot number (base is defaulted to first keys slot)
// This is useful to quickly determine a singe slot for multi keys operations.
const slotForRedisMulti = calculateMultipleSlots([


OLD in these benchmarks refers to the ioredis crc calc and many of the other calculators that use Buffer.
node -v                                                                                                                                                                                                ✔  16.38G RAM  10:29:07

NEW tags x 721,445 ops/sec ±0.44% (90 runs sampled)
OLD tags x 566,777 ops/sec ±0.97% (96 runs sampled)
NEW without tags x 2,054,845 ops/sec ±1.77% (92 runs sampled)
OLD without tags x 865,839 ops/sec ±0.43% (96 runs sampled)
NEW without tags singular x 6,354,097 ops/sec ±1.25% (94 runs sampled)
OLD without tags singular x 4,012,250 ops/sec ±0.96% (94 runs sampled)
NEW tags (Buffer) x 552,346 ops/sec ±1.35% (92 runs sampled)