code: function(options) {
            var self = this
            var result = []
            if (options._id) {
              var id = Array.isArray(options._id) ? options._id : [options._id]
              id.forEach(function(id) {
                if (self.cache[id]) {
                  result.push(self.cache[id])
                }
              })
            } else {
              result = Object.keys(this.cache).map(function(k) {
                return self.cache[k]
              }).sort(function(count1, count2) {
                return count1._id - count2._id
              })
              if (options.skip || options.limit) {
                var skip = options.skip || 0
                var limit = options.limit || 0
                return result.slice(skip, skip + limit)
              }
            }
            return result
          }
docs: pre-find-memCacheCounterAdvanced