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 performance measurements

Each table row shows performance measurements for this Go program with a particular command-line input value N.

 N  CPU secs Elapsed secs Memory KB Code B ≈ CPU Load
120.310.10?688  78% 78% 70% 80%
167.202.4320,408688  73% 78% 73% 75%
20153.9642.45307,056688  91% 90% 93% 90%

Read the ↓ make, command line, and program output logs to see how this program was run.

Read binary-trees benchmark to see what this program should do.

 notes

go version go1.2 linux/386

 binary-trees Go #4 program source code

/* The Computer Language Benchmarks Game
 * http://benchmarksgame.alioth.debian.org/
 *
 * based on Go program by The Go Authors.
 * based on C program by Kevin Carson
 * flag.Arg hack by Isaac Gouy
 * modified by Jamil Djadala to use goroutines
 * modified by Chai Shushan
 *
 */

package main

import (
   "flag"
   "fmt"
   "runtime"
   "strconv"
   "sync"
)

var minDepth = 4
var n = 0

func main() {
   runtime.GOMAXPROCS(runtime.NumCPU() * 2)

   flag.Parse()
   if flag.NArg() > 0 {
      n, _ = strconv.Atoi(flag.Arg(0))
   }

   maxDepth := n
   if minDepth+2 > n {
      maxDepth = minDepth + 2
   }
   stretchDepth := maxDepth + 1

   check_l := bottomUpTree(0, stretchDepth).ItemCheck()
   fmt.Printf("stretch tree of depth %d\t check: %d\n", stretchDepth, check_l)

   longLivedTree := bottomUpTree(0, maxDepth)

   result_trees := make([]int, maxDepth+1)
   result_check := make([]int, maxDepth+1)

   var wg sync.WaitGroup
   for depth_l := minDepth; depth_l <= maxDepth; depth_l += 2 {
      wg.Add(1)
      go func(depth int) {
         iterations := 1 << uint(maxDepth-depth+minDepth)
         check := 0

         for i := 1; i <= iterations; i++ {
            check += bottomUpTree(i, depth).ItemCheck()
            check += bottomUpTree(-i, depth).ItemCheck()
         }
         result_trees[depth] = iterations * 2
         result_check[depth] = check

         wg.Done()
      }(depth_l)
   }
   wg.Wait()

   for depth := minDepth; depth <= maxDepth; depth += 2 {
      fmt.Printf("%d\t trees of depth %d\t check: %d\n",
         result_trees[depth], depth, result_check[depth],
      )
   }
   fmt.Printf("long lived tree of depth %d\t check: %d\n",
      maxDepth, longLivedTree.ItemCheck(),
   )
}

func bottomUpTree(item, depth int) *Node {
   if depth <= 0 {
      return &Node{item, nil, nil}
   }
   return &Node{item,
      bottomUpTree(2*item-1, depth-1),
      bottomUpTree(2*item, depth-1),
   }
}

type Node struct {
   item        int
   left, right *Node
}

func (self *Node) ItemCheck() int {
   if self.left == nil {
      return self.item
   }
   return self.item + self.left.ItemCheck() - self.right.ItemCheck()
}

 make, command-line, and program output logs

Mon, 02 Dec 2013 07:52:07 GMT

MAKE:
/usr/local/src/go/bin/go build -o binarytrees.go-4.go_run
0.41s to complete and log all make actions

COMMAND LINE:
./binarytrees.go-4.go_run 20

PROGRAM OUTPUT:
stretch tree of depth 21	 check: -1
2097152	 trees of depth 4	 check: -2097152
524288	 trees of depth 6	 check: -524288
131072	 trees of depth 8	 check: -131072
32768	 trees of depth 10	 check: -32768
8192	 trees of depth 12	 check: -8192
2048	 trees of depth 14	 check: -2048
512	 trees of depth 16	 check: -512
128	 trees of depth 18	 check: -128
32	 trees of depth 20	 check: -32
long lived tree of depth 20	 check: -1

Revised BSD license

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