Пример #1
0
 public void testConsistentHash_probabilities() {
   AtomicLongMap<Integer> map = AtomicLongMap.create();
   Random r = new Random(9);
   for (int i = 0; i < ITERS; i++) {
     countRemaps(r.nextLong(), map);
   }
   for (int shard = 2; shard <= MAX_SHARDS; shard++) {
     // Rough: don't exceed 1.2x the expected number of remaps by more than 20
     assertTrue(map.get(shard) <= 1.2 * ITERS / shard + 20);
   }
 }
Пример #2
0
 private void countRemaps(long h, AtomicLongMap<Integer> map) {
   int last = 0;
   for (int shards = 2; shards <= MAX_SHARDS; shards++) {
     int chosen = Hashing.consistentHash(h, shards);
     if (chosen != last) {
       map.incrementAndGet(shards);
       last = chosen;
     }
   }
 }