| // +build ignore |
| |
| /* |
| Copyright 2013 Google Inc. |
| |
| Licensed under the Apache License, Version 2.0 (the "License"); |
| you may not use this file except in compliance with the License. |
| You may obtain a copy of the License at |
| |
| http://www.apache.org/licenses/LICENSE-2.0 |
| |
| Unless required by applicable law or agreed to in writing, software |
| distributed under the License is distributed on an "AS IS" BASIS, |
| WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| See the License for the specific language governing permissions and |
| limitations under the License. |
| */ |
| |
| package consistenthash |
| |
| import ( |
| "fmt" |
| "strconv" |
| "testing" |
| ) |
| |
| func TestHashing(t *testing.T) { |
| |
| // Override the hash function to return easier to reason about values. Assumes |
| // the keys can be converted to an integer. |
| hash := New(3, func(key []byte) uint32 { |
| i, err := strconv.Atoi(string(key)) |
| if err != nil { |
| panic(err) |
| } |
| return uint32(i) |
| }) |
| |
| // Given the above hash function, this will give replicas with "hashes": |
| // 2, 4, 6, 12, 14, 16, 22, 24, 26 |
| hash.Add("6", "4", "2") |
| |
| testCases := map[string]string{ |
| "2": "2", |
| "11": "2", |
| "23": "4", |
| "27": "2", |
| } |
| |
| for k, v := range testCases { |
| if hash.Get(k) != v { |
| t.Errorf("Asking for %s, should have yielded %s", k, v) |
| } |
| } |
| |
| // Adds 8, 18, 28 |
| hash.Add("8") |
| |
| // 27 should now map to 8. |
| testCases["27"] = "8" |
| |
| for k, v := range testCases { |
| if hash.Get(k) != v { |
| t.Errorf("Asking for %s, should have yielded %s", k, v) |
| } |
| } |
| |
| } |
| |
| func TestConsistency(t *testing.T) { |
| hash1 := New(1, nil) |
| hash2 := New(1, nil) |
| |
| hash1.Add("Bill", "Bob", "Bonny") |
| hash2.Add("Bob", "Bonny", "Bill") |
| |
| if hash1.Get("Ben") != hash2.Get("Ben") { |
| t.Errorf("Fetching 'Ben' from both hashes should be the same") |
| } |
| |
| hash2.Add("Becky", "Ben", "Bobby") |
| |
| if hash1.Get("Ben") != hash2.Get("Ben") || |
| hash1.Get("Bob") != hash2.Get("Bob") || |
| hash1.Get("Bonny") != hash2.Get("Bonny") { |
| t.Errorf("Direct matches should always return the same entry") |
| } |
| |
| } |
| |
| func BenchmarkGet8(b *testing.B) { benchmarkGet(b, 8) } |
| func BenchmarkGet32(b *testing.B) { benchmarkGet(b, 32) } |
| func BenchmarkGet128(b *testing.B) { benchmarkGet(b, 128) } |
| func BenchmarkGet512(b *testing.B) { benchmarkGet(b, 512) } |
| |
| func benchmarkGet(b *testing.B, shards int) { |
| |
| hash := New(50, nil) |
| |
| var buckets []string |
| for i := 0; i < shards; i++ { |
| buckets = append(buckets, fmt.Sprintf("shard-%d", i)) |
| } |
| |
| hash.Add(buckets...) |
| |
| b.ResetTimer() |
| |
| for i := 0; i < b.N; i++ { |
| hash.Get(buckets[i&(shards-1)]) |
| } |
| } |