Datahike memory benchmark

datahike-mem-bench.clj

(require '[datahike.api :as d])
(import '[java.util Random]))

(taoensso.timbre/set-level! :warn)

;; Thanks to https://stackoverflow.com/a/64034927/10978897
(defn rand-str
  ^String [^Long len]
  (let [leftLimit 97
        rightLimit 122
        random (Random.)
        stringBuilder (StringBuilder. len)
        diff (- rightLimit leftLimit)]
    (dotimes [_ len]
      (let [ch (char (.intValue ^Double (+ leftLimit (* (.nextFloat ^Random random) (+ diff 1)))))]
        (.append ^StringBuilder stringBuilder ch)))
    (.toString ^StringBuilder stringBuilder)))

(def cfg {:store {:backend :file
                  :path "/tmp/mem-bench"}
          :keep-history? true
          :attribute-refs? false
          :schema-flexibility :write})

(def schema [{:db/ident :block/text
              :db/valueType :db.type/string
              :db/cardinality :db.cardinality/one}
             {:db/ident :block/counter
              :db/valueType :db.type/long
              :db/cardinality :db.cardinality/one}
             {:db/ident :block/id
              :db/valueType :db.type/long
              :db/unique :db.unique/identity
              :db/cardinality :db.cardinality/one}])

(d/delete-database cfg)

(d/create-database cfg)

(def conn (d/connect cfg))

(d/transact conn {:tx-data schema})

(doseq [n (range 500000)]
  (d/transact conn {:tx-data (vec (concat [{:block/text (rand-str (rand-int 10000))
                                            :block/id (mod n 50000)
                                            :block/counter n}]
                                          (when (< 5000 n)
                                            [[:db/retractEntity [:block/id (mod n 5000)]]])))}))