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1 //  Benchmark for integer sorting speed across parallel threads.
2 //
3 //  Copyright Steven Ross 2014
4 //
5 // Distributed under the Boost Software License, Version 1.0.
6 //    (See accompanying file LICENSE_1_0.txt or copy at
7 //          http://www.boost.org/LICENSE_1_0.txt)
8 
9 //  See http://www.boost.org/libs/sort for library home page.
10 
11 #include <boost/random/mersenne_twister.hpp>
12 #include <boost/random/uniform_int_distribution.hpp>
13 #include <boost/sort/spreadsort/spreadsort.hpp>
14 #include <boost/thread.hpp>
15 #include <time.h>
16 #include <stdio.h>
17 #include <stdlib.h>
18 #include <algorithm>
19 #include <vector>
20 #include <iostream>
21 #include <fstream>
22 #include <string>
23 using std::string;
24 using namespace boost::sort::spreadsort;
25 
26 #define DATA_TYPE string
27 
is_sorted(const std::vector<DATA_TYPE> & array)28 static bool is_sorted(const std::vector<DATA_TYPE> &array) {
29   for (unsigned u = 0; u + 1 < array.size(); ++u) {
30     if (array[u] > array[u + 1]) {
31       return false;
32     }
33   }
34   return true;
35 }
36 
sort_core(std::vector<DATA_TYPE> & array,bool stdSort,unsigned loopCount)37 static void sort_core(std::vector<DATA_TYPE> &array, bool stdSort,
38                unsigned loopCount) {
39   if (stdSort)
40     std::sort(array.begin(), array.end());
41   else
42     boost::sort::spreadsort::spreadsort(array.begin(), array.end());
43   if (!is_sorted(array)) {
44     fprintf(stderr, "sort failed!\n");
45     exit(1);
46   }
47 }
48 
sort_loop(const std::vector<DATA_TYPE> & base_array,bool stdSort,unsigned loopCount)49 static void sort_loop(const std::vector<DATA_TYPE> &base_array, bool stdSort,
50                unsigned loopCount) {
51   std::vector<DATA_TYPE> array(base_array);
52   for (unsigned u = 0; u < loopCount; ++u) {
53     for (unsigned v = 0; v < base_array.size(); ++v) {
54       array[v] = base_array[v];
55     }
56     sort_core(array, stdSort, loopCount);
57   }
58 }
59 
60 //Pass in an argument to test std::sort
main(int argc,const char ** argv)61 int main(int argc, const char ** argv) {
62   std::ifstream indata;
63   std::ofstream outfile;
64   bool stdSort = false;
65   int constant_to_random_ratio = -1;
66   int threadCount = -1;
67   unsigned loopCount = 0;
68   for (int u = 1; u < argc; ++u) {
69     if (std::string(argv[u]) == "-std")
70       stdSort = true;
71     else if(threadCount < 0)
72       threadCount = atoi(argv[u]);
73     else if (!loopCount)
74       loopCount = atoi(argv[u]);
75     else
76       constant_to_random_ratio = atoi(argv[u]);
77   }
78   if (!loopCount) {
79     loopCount = 1;
80   }
81   printf("threads: %d loops: %d\n", threadCount, loopCount);
82 
83   std::vector<DATA_TYPE> base_array;
84   if (constant_to_random_ratio >= 0) {
85     //Test for random data with gaps of identical data.
86     random::mt19937 generator;
87     random::uniform_int_distribution<int> distribution(0,255);
88     const int constant_to_random_count = 1000000;
89     const int string_length = 1000;
90     for (int i = 0; i < constant_to_random_count; ++i) {
91       DATA_TYPE temp(string_length, 'x');  // fill with default character.
92       for (int j = constant_to_random_ratio; j < string_length;) {
93         int val = distribution(generator);
94         temp[j] = val;
95         j += (val * constant_to_random_ratio)/128 + 1;
96       }
97       base_array.push_back(temp);
98     }
99   } else {
100     indata.open("input.txt", std::ios_base::in | std::ios_base::binary);
101     if (indata.bad()) {
102       printf("input.txt could not be opened\n");
103       return 1;
104     }
105     DATA_TYPE inval;
106     while (!indata.eof() ) {
107       indata >> inval;
108       base_array.push_back(inval);
109     }
110   }
111 
112   // Sort the input
113   clock_t start, end;
114   double elapsed;
115   std::vector<boost::thread *> workers;
116   start = clock();
117   if (threadCount == 0) {
118     if (loopCount > 1) {
119       sort_loop(base_array, stdSort, loopCount);
120     } else {
121       sort_core(base_array, stdSort, loopCount);
122     }
123     threadCount = 1;
124   } else {
125     for (int i = 0; i < threadCount; ++i) {
126       workers.push_back(new boost::thread(sort_loop, base_array, stdSort,
127                                           loopCount));
128     }
129     for (int i = 0; i < threadCount; ++i) {
130       workers[i]->join();
131       delete workers[i];
132     }
133   }
134   end = clock();
135   elapsed = static_cast<double>(end - start) ;
136 
137   printf("for %lu strings\n", base_array.size());
138   if (stdSort)
139     printf("std::sort clock time %lf\n", elapsed/CLOCKS_PER_SEC/threadCount);
140   else
141     printf("spreadsort clock time %lf\n", elapsed/CLOCKS_PER_SEC/threadCount);
142   return 0;
143 }
144