Evaluating the design

High performance

  • Consistent Hashing results in O(log(N)) complexity where N represents the number of shards
  • On a hash server, it takes constant time to retrieve a value using the key O(1)
  • for eviction in the linked list

Let’s assess the effective access time considering there could be cache hits and misses.

EAT = Ratio (hit) x Time (hit) + Ratio(miss) x Time (miss)

if MFU, we have 10% cache miss and for LRU, 5% cache miss rate

MFU-EAT = 0.9 x 5ms + 0.1 x 30ms 0.9 x 0.005 + 0.1 x 0.030 0.0045 + 0.003 = 0.0075 - 7.5 ms

LRU-EAT = 0.95 x 5ms + 0.05 x 30ms 0.95 x 0.005 + 0.05 x 0.03 0.00475 + 0.0015 = 0.00625 = 6.25ms

Scalability