PageRenderTime 28ms CodeModel.GetById 0ms RepoModel.GetById 0ms app.codeStats 0ms

/libstdc++-v3/doc/html/ext/pb_ds/priority_queue_random_int_push_pop_timing_test.html

https://bitbucket.org/pizzafactory/pf-gcc
HTML | 161 lines | 160 code | 1 blank | 0 comment | 0 complexity | 711643ebbe7afeb2854c037a43a9991e MD5 | raw file
    

  1. <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    2. 

  2.     "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
    3. 

  3. 

  4. <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
    5. 

  5. <head>
    6. 

  6. <meta name="generator" content="HTML Tidy for Linux/x86 (vers 12 April 2005), see www.w3.org" />
    7. 

  7. <title>Priority Queue Random Int Push Pop Timing Test</title>
    8. 

  8. <meta http-equiv="Content-Type" content="text/html; charset=us-ascii" />
    9. 

  9. </head>
    10. 

  10. <body>
    11. 

  11. <div id="page">
    12. 

  12. <h1>Priority Queue Random Integer <tt>push</tt> and
    13. 

  13.     <tt>pop</tt> Timing Test</h1>
    14. 

  14. <h2><a name="description" id="description">Description</a></h2>
    15. 

  15. <p>This test inserts a number of values with i.i.d. integer
    16. 

  16.     keys into a container using <tt>push</tt> , then removes them
    17. 

  17.     using <tt>pop</tt> . It measures the average time for
    18. 

  18.     <tt>push</tt> and <tt>pop</tt> as a function of the number of
    19. 

  19.     values.</p>
    20. 

  20. <p>(The test was executed with <a href="http://gcc.gnu.org/viewcvs/*checkout*/trunk/libstdc%2B%2B-v3/testsuite/performance/ext/pb_ds/priority_queue_random_int_push_pop_timing.cc">
    21. 

  21. <tt>priority_queue_random_int_push_pop_timing_test</tt></a>
    22. 

  22.     thirty_years_among_the_dead_preproc.txt 200 200 2100)</p>
    23. 

  23. <h2><a name="purpose" id="purpose">Purpose</a></h2>
    24. 

  24. <p>The test checks the effect of different underlying
    25. 

  25.     data structures (see <a href="pq_design.html#pq_imp">Design::Priority
    26. 

  26.     Queues::Implementations</a>).</p>
    27. 

  27. <h2><a name="results" id="results">Results</a></h2>
    28. 

  28. <p>Figures <a href="#NPG">NPG</a>, <a href="#NPM">NPM</a>, and
    29. 

  29.     <a href="#NPL">NPL</a> shows the results for the native
    30. 

  30.     priority queues and <tt>pb_ds</tt> 's priority queues in
    31. 

  31.     <a href="pq_performance_tests.html#gcc"><u>g++</u></a>,
    32. 

  32.     <a href="pq_performance_tests.html#msvc"><u>msvc++</u></a>, and
    33. 

  33.     <a href="pq_performance_tests.html#local"><u>local</u></a>,
    34. 

  34.     respectively.</p>
    35. 

  35. <div id="NPG_res_div">
    36. 

  36. <div id="NPG_gcc">
    37. 

  37. <div id="NPG_priority_queue_random_int_push_pop_timing_test">
    38. 

  38. <div id="NPG_pq">
    39. 

  39. <div id="NPG_Native_and__tt_pb_ds_455tt__priority_queue__tt_push_455tt___tt_pop_455tt__timing_test"><div style="border-style: dotted; border-width: 1px; border-color: lightgray"><h6 class="c1"><a name="NPG" id="NPG"><img src="priority_queue_random_int_push_pop_timing_test_gcc.png" alt="no image" /></a></h6>NPG: Native and <tt>pb ds</tt> priority queue <tt>push</tt> <tt>pop</tt> timing test - <a href="pq_performance_tests.html#gcc">g++</a><p>In the above figure, the names in the legends have the following meaning:</p>
    40. 

  40. <ol>
    41. 

  41. <li>
    42. 

  42. thin_heap-
    43. 

  43. <a href="priority_queue.html"><tt>priority_queue</tt></a>
    44. 

  44.  with <tt>Tag</tt> = <a href="thin_heap_tag.html"><tt>thin_heap_tag</tt></a>
    45. 

  45. </li>
    46. 

  46. <li>
    47. 

  47. rc_binomial_heap-
    48. 

  48. <a href="priority_queue.html"><tt>priority_queue</tt></a>
    49. 

  49.  with <tt>Tag</tt> = <a href="rc_binomial_heap_tag.html"><tt>rc_binomial_heap_tag</tt></a>
    50. 

  50. </li>
    51. 

  51. <li>
    52. 

  52. binomial_heap-
    53. 

  53. <a href="priority_queue.html"><tt>priority_queue</tt></a>
    54. 

  54.  with <tt>Tag</tt> = <a href="binomial_heap_tag.html"><tt>binomial_heap_tag</tt></a>
    55. 

  55. </li>
    56. 

  56. <li>
    57. 

  57. pairing_heap-
    58. 

  58. <a href="priority_queue.html"><tt>priority_queue</tt></a>
    59. 

  59.  with <tt>Tag</tt> = <a href="pairing_heap_tag.html"><tt>pairing_heap_tag</tt></a>
    60. 

  60. </li>
    61. 

  61. <li>
    62. 

  62. n_pq_deque-
    63. 

  63. <tt>std::priority_queue</tt> adapting <tt>std::deque</tt></li>
    64. 

  64. <li>
    65. 

  65. n_pq_vector-
    66. 

  66. <tt>std::priority_queue</tt> adapting <tt>std::vector</tt></li>
    67. 

  67. <li>
    68. 

  68. binary_heap-
    69. 

  69. <a href="priority_queue.html"><tt>priority_queue</tt></a>
    70. 

  70.  with <tt>Tag</tt> = <a href="binary_heap_tag.html"><tt>binary_heap_tag</tt></a>
    71. 

  71. </li>
    72. 

  72. </ol>
    73. 

  73. </div><div style="width: 100%; height: 20px"></div></div>
    74. 

  74. </div>
    75. 

  75. </div>
    76. 

  76. </div>
    77. 

  77. </div>
    78. 

  78. <div id="NPM_res_div">
    79. 

  79. <div id="NPM_msvc">
    80. 

  80. <div id="NPM_priority_queue_random_int_push_pop_timing_test">
    81. 

  81. <div id="NPM_pq">
    82. 

  82. <div id="NPM_Native_and__tt_pb_ds_455tt__priority_queue__tt_push_455tt___tt_pop_455tt__timing_test"><div style="border-style: dotted; border-width: 1px; border-color: lightgray"><h6 class="c1"><a name="NPM" id="NPM"><img src="priority_queue_random_int_push_pop_timing_test_msvc.png" alt="no image" /></a></h6>NPM: Native and <tt>pb ds</tt> priority queue <tt>push</tt> <tt>pop</tt> timing test - <a href="pq_performance_tests.html#msvc">msvc++</a><p>In the above figure, the names in the legends have the following meaning:</p>
    83. 

  83. <ol>
    84. 

  84. <li>
    85. 

  85. thin_heap-
    86. 

  86. <a href="priority_queue.html"><tt>priority_queue</tt></a>
    87. 

  87.  with <tt>Tag</tt> = <a href="thin_heap_tag.html"><tt>thin_heap_tag</tt></a>
    88. 

  88. </li>
    89. 

  89. <li>
    90. 

  90. rc_binomial_heap-
    91. 

  91. <a href="priority_queue.html"><tt>priority_queue</tt></a>
    92. 

  92.  with <tt>Tag</tt> = <a href="rc_binomial_heap_tag.html"><tt>rc_binomial_heap_tag</tt></a>
    93. 

  93. </li>
    94. 

  94. <li>
    95. 

  95. binomial_heap-
    96. 

  96. <a href="priority_queue.html"><tt>priority_queue</tt></a>
    97. 

  97.  with <tt>Tag</tt> = <a href="binomial_heap_tag.html"><tt>binomial_heap_tag</tt></a>
    98. 

  98. </li>
    99. 

  99. <li>
    100. 

  100. pairing_heap-
    101. 

  101. <a href="priority_queue.html"><tt>priority_queue</tt></a>
    102. 

  102.  with <tt>Tag</tt> = <a href="pairing_heap_tag.html"><tt>pairing_heap_tag</tt></a>
    103. 

  103. </li>
    104. 

  104. <li>
    105. 

  105. n_pq_deque-
    106. 

  106. <tt>std::priority_queue</tt> adapting <tt>std::deque</tt></li>
    107. 

  107. <li>
    108. 

  108. n_pq_vector-
    109. 

  109. <tt>std::priority_queue</tt> adapting <tt>std::vector</tt></li>
    110. 

  110. <li>
    111. 

  111. binary_heap-
    112. 

  112. <a href="priority_queue.html"><tt>priority_queue</tt></a>
    113. 

  113.  with <tt>Tag</tt> = <a href="binary_heap_tag.html"><tt>binary_heap_tag</tt></a>
    114. 

  114. </li>
    115. 

  115. </ol>
    116. 

  116. </div><div style="width: 100%; height: 20px"></div></div>
    117. 

  117. </div>
    118. 

  118. </div>
    119. 

  119. </div>
    120. 

  120. </div>
    121. 

  121. <div id="NPL_res_div">
    122. 

  122. <div id="NPL_local">
    123. 

  123. <div id="NPL_priority_queue_random_int_push_pop_timing_test">
    124. 

  124. <div id="NPL_pq">
    125. 

  125. <div id="NPL_Native_and__tt_pb_ds_455tt__priority_queue__tt_push_455tt___tt_pop_455tt__timing_test"><div style = "border-style: dotted; border-width: 1px; border-color: lightgray"><h6 class="c1"><a name="NPL" id= "NPL"><img src="priority_queue_random_int_push_pop_timing_test_local.png" alt="no image" /></a></h6>NPL: Native and <tt>pb ds</tt> priority queue <tt>push</tt> <tt>pop</tt> timing test - <a href = "pq_performance_tests.html#local">local</a></div><div style = "width: 100%; height: 20px"></div></div>
    126. 

  126. </div>
    127. 

  127. </div>
    128. 

  128. </div>
    129. 

  129. </div>
    130. 

  130. <h2><a name="observations" id="observations">Observations</a></h2>
    131. 

  131. <p>Binary heaps are the most suited for sequences of
    132. 

  132.     <tt>push</tt> and <tt>pop</tt> operations of primitive types
    133. 

  133.     (<i>e.g.</i> <tt><b>int</b></tt>s). This is explained in
    134. 

  134.     <a href="priority_queue_random_int_push_timing_test.html">Priority
    135. 

  135.     Queue Random Int <tt>push</tt> Timing Test</a> . (See <a href="priority_queue_text_push_pop_timing_test.html">Priority Queue
    136. 

  136.     Text <tt>push</tt> Timing Test</a> for the case of primitive
    137. 

  137.     types.)</p>
    138. 

  138. <p>At first glance it seems that the STL's vector-based
    139. 

  139.     priority queue is approximately on par with <tt>pb_ds</tt>'s
    140. 

  140.     corresponding priority queue. There are two differences
    141. 

  141.     however:</p>
    142. 

  142. <ol>
    143. 

  143. <li>The STL's priority queue does not downsize the underlying
    144. 

  144.       vector (or deque) as the priority queue becomes smaller
    145. 

  145.       (see <a href="priority_queue_text_pop_mem_usage_test.html">Priority Queue
    146. 

  146.       Text <tt>pop</tt> Memory Use Test</a>). It is therefore
    147. 

  147.       gaining some speed at the expense of space.</li>
    148. 

  148. <li>From <a href="priority_queue_random_int_push_pop_timing_test.html">Priority
    149. 

  149.       Queue Random Integer <tt>push</tt> and <tt>pop</tt> Timing
    150. 

  150.       Test</a>, it seems that the STL's priority queue is slower in
    151. 

  151.       terms of <tt>pus</tt> operations. Since the number of
    152. 

  152.       <tt>pop</tt> operations is at most that of <tt>push</tt>
    153. 

  153.       operations, the test here is the "best" for the STL's
    154. 

  154.       priority queue.</li>
    155. 

  155. </ol>
    156. 

  156. <p><a href="pq_performance_tests.html#pq_observations">Priority-Queue
    157. 

  157.     Performance Tests::Observations</a> discusses this further and
    158. 

  158.     summarizes.</p>
    159. 

  159. </div>
    160. 

  160. </body>
    161. 

  161. </html>
    162. 

  162.