Overview
doublejump is a revamped Google’s jump consistent hash. It overcomes the shortcoming of the original implementation - not being able to remove nodes.
Benchmark
BenchmarkDoubleJumpWithoutLock/10-nodes 50000000 27.6 ns/op
BenchmarkDoubleJumpWithoutLock/100-nodes 30000000 42.7 ns/op
BenchmarkDoubleJumpWithoutLock/1000-nodes 30000000 54.1 ns/op
BenchmarkDoubleJump/10-nodes 20000000 72.9 ns/op
BenchmarkDoubleJump/100-nodes 20000000 86.1 ns/op
BenchmarkDoubleJump/1000-nodes 20000000 97.9 ns/op
BenchmarkStathatConsistent/10-nodes 5000000 301 ns/op
BenchmarkStathatConsistent/100-nodes 5000000 334 ns/op
BenchmarkStathatConsistent/1000-nodes 3000000 444 ns/op
BenchmarkSerialxHashring/10-nodes 5000000 280 ns/op
BenchmarkSerialxHashring/100-nodes 5000000 340 ns/op
BenchmarkSerialxHashring/1000-nodes 3000000 427 ns/op
Example
h := NewHash()
for i := 0; i < 10; i++ {
h.Add(fmt.Sprintf("node%d", i))
}
fmt.Println(h.Len())
fmt.Println(h.LooseLen())
fmt.Println(h.Get(1000))
fmt.Println(h.Get(2000))
fmt.Println(h.Get(3000))
h.Remove("node3")
fmt.Println(h.Len())
fmt.Println(h.LooseLen())
fmt.Println(h.Get(1000))
fmt.Println(h.Get(2000))
fmt.Println(h.Get(3000))
// Output:
// 10
// 10
// node9
// node2
// node3
// 9
// 10
// node9
// node2
// node0