Two datoms in the same transaction conflict

[yayitswei]

Trying to figure out how to use monocopy in parallel.

(defn test-monocopy [n conn]
  (doall
    (pmap
      (fn [_]
        (d/t conn
             (concat (mc/datoms {(rand) (rand)}
                                (d/tempid :db.part/user) :obj/ref))))
          (range n))))

This snippet will often produce an exception on my machine:

user=> (test-monocopy 20 conn)
ExceptionInfo :transact/datoms-conflict Two datoms in the same transaction conflict: {:d1 #Datum{:e 17592186045497 :a 76 :v :tailrecursion.monocopy/map :tx 13194139535222 :added true}, :d2 #Datum{:e 17592186045497 :a 76 :v :tailrecursion.monocopy/entry :tx 13194139535222 :added true}}  clojure.core/ex-info (core.clj:4327)