antirez/redis — pull request #2155 by janoberst (2014-11-21 00:22:21+00:00)
Title: Add last_eviction_age statistic to INFO

When using Redis as an LRU cache it is helpful to know how old item was that was most recently evicted.

We care about having at least 24 hours worth of data in the Redis LRU, so we monitor this statistic to gauge how old the current dataset roughly is: If the most recently evicted key is younger than 24 hours we need to change our setup.