multithreading - Multithreaded merge-sort algorithm in Clojure -

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i need write implementation of merge-sort algorithm in clojure in single thread , using parallelism options 2, 4, 8, 16, , 32 threads.
program read large collection of integers (1 million) text file , put them list sorting.
newbie on clojure , functional programming @ all.
i've written code reading file ...

(use 'clojure.java.io) (defn get-lines [fname]   (with-open [r (reader fname)]     (doall (map read-string (line-seq r))))) (def numbers (get-lines "numbers.dat"))


... , found single thread implementation.
can't realize parallel algorithm. seems beyond me.
me?

if looking for...

(use 'clojure.java.io)  (defn get-lines [fname]   (with-open [r (reader fname)]     (doall (map read-string (line-seq r)))))  (def numbers (get-lines "numbers.dat"))  (defn merge-lists [left right]   (loop [head [] l left r right]     (if (empty? l) (concat head r)     (if (empty? r) (concat head l)     (if (> (first l) (first r))       (recur (conj head (first r)) l (rest r))       (recur (conj head (first l)) (rest l) r))))))  (defn naive-merge-sort [list]   (if (< (count list) 2) list     (apply merge-lists       (map naive-merge-sort         (split-at (/ (count list) 2) list)))))  (defn parallel-merge-sort-2 [list]   (if (< (count list) 2) list     (apply merge-lists       (pmap naive-merge-sort         (split-at (/ (count list) 2) list)))))  (defn parallel-merge-sort-4 [list]   (if (< (count list) 2) list     (apply merge-lists       (pmap parallel-merge-sort-2         (split-at (/ (count list) 2) list)))))  (defn parallel-merge-sort-8 [list]   (if (< (count list) 2) list     (apply merge-lists       (pmap parallel-merge-sort-4         (split-at (/ (count list) 2) list)))))  (defn parallel-merge-sort-16 [list]   (if (< (count list) 2) list     (apply merge-lists       (pmap parallel-merge-sort-8         (split-at (/ (count list) 2) list)))))  (defn parallel-merge-sort-32 [list]   (if (< (count list) 2) list     (apply merge-lists       (pmap parallel-merge-sort-16         (split-at (/ (count list) 2) list)))))

naive-merge-sort single threaded implementation. parallel implementations breaks input list 2-32 chunks sorted using naive-merge-sort.


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