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

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  12 <h1>Priority Queue Text <tt>push</tt> Timing Test</h1>
  13 <h2><a name="description" id="description">Description</a></h2>
  14 <p>This test inserts a number of values with keys from an
  15     arbitrary text ([ <a href="references.html#wickland96thirty">wickland96thirty</a> ]) into
  16     a container using <tt>push</tt> . It measures the average time
  17     for <tt>push</tt> as a function of the number of values
  18     pushed.</p>
  19 <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_text_push_timing.cc"><tt>priority_queue_text_push_timing_test</tt></a>
  20     thirty_years_among_the_dead_preproc.txt 200 200 2100)</p>
  21 <h2><a name="purpose" id="purpose">Purpose</a></h2>
  22 <p>The test checks the effect of different underlying
  23     data structures (see <a href="pq_design.html#pq_imp">Design::Priority
  24     Queues::Implementations</a>).</p>
  25 <h2><a name="results" id="results">Results</a></h2>
  26 <p>Figures <a href="#NPG">NPG</a>, <a href="#NPM">NPM</a>, and
  27     <a href="#NPL">NPL</a> show the results for the native priority
  28     queues and <tt>pb_ds</tt> 's priority queues in <a href="pq_performance_tests.html#gcc"><u>g++</u></a>, <a href="pq_performance_tests.html#msvc"><u>msvc++</u></a>, and
  29     <a href="pq_performance_tests.html#local"><u>local</u></a>,
  30     respectively; Figures <a href="#NBRG">NBRG</a>, <a href="#NBRM">NBRM</a>, and <a href="#NBRL">NBRL</a> shows the
  31     results for the binary-heap based native priority queues and
  32     <tt>pb_ds</tt>'s pairing-heap priority queues in <a href="pq_performance_tests.html#gcc"><u>g++</u></a>, <a href="pq_performance_tests.html#msvc"><u>msvc++</u></a>, and
  33     <a href="pq_performance_tests.html#local"><u>local</u></a>,
  34     respectively</p>
  35 <div id="NPG_res_div">
  36 <div id="NPG_gcc">
  37 <div id="NPG_priority_queue_text_push_timing_test">
  38 <div id="NPG_pq">
  39 <div id="NPG_Native_and__tt_pb_ds_455tt__priority_queue__tt_push_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_text_push_timing_test_gcc.png" alt="no image" /></a></h6>NPG: Native and <tt>pb ds</tt> priority queue <tt>push</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 <ol>
  41 <li>
  42 n_pq_vector-
  43 <tt>std::priority_queue</tt> adapting <tt>std::vector</tt></li>
  44 <li>
  45 n_pq_deque-
  46 <tt>std::priority_queue</tt> adapting <tt>std::deque</tt></li>
  47 <li>
  48 binary_heap-
  49 <a href="priority_queue.html"><tt>priority_queue</tt></a>
  50  with <tt>Tag</tt> = <a href="binary_heap_tag.html"><tt>binary_heap_tag</tt></a>
  51 </li>
  52 <li>
  53 rc_binomial_heap-
  54 <a href="priority_queue.html"><tt>priority_queue</tt></a>
  55  with <tt>Tag</tt> = <a href="rc_binomial_heap_tag.html"><tt>rc_binomial_heap_tag</tt></a>
  56 </li>
  57 <li>
  58 thin_heap-
  59 <a href="priority_queue.html"><tt>priority_queue</tt></a>
  60  with <tt>Tag</tt> = <a href="thin_heap_tag.html"><tt>thin_heap_tag</tt></a>
  61 </li>
  62 <li>
  63 binomial_heap-
  64 <a href="priority_queue.html"><tt>priority_queue</tt></a>
  65  with <tt>Tag</tt> = <a href="binomial_heap_tag.html"><tt>binomial_heap_tag</tt></a>
  66 </li>
  67 <li>
  68 pairing_heap-
  69 <a href="priority_queue.html"><tt>priority_queue</tt></a>
  70  with <tt>Tag</tt> = <a href="pairing_heap_tag.html"><tt>pairing_heap_tag</tt></a>
  71 </li>
  72 </ol>
  73 </div><div style="width: 100%; height: 20px"></div></div>
  74 </div>
  75 </div>
  76 </div>
  77 </div>
  78 <div id="NPM_res_div">
  79 <div id="NPM_msvc">
  80 <div id="NPM_priority_queue_text_push_timing_test">
  81 <div id="NPM_pq">
  82 <div id="NPM_Native_and__tt_pb_ds_455tt__priority_queue__tt_push_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_text_push_timing_test_msvc.png" alt="no image" /></a></h6>NPM: Native and <tt>pb ds</tt> priority queue <tt>push</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 <ol>
  84 <li>
  85 n_pq_deque-
  86 <tt>std::priority_queue</tt> adapting <tt>std::deque</tt></li>
  87 <li>
  88 rc_binomial_heap-
  89 <a href="priority_queue.html"><tt>priority_queue</tt></a>
  90  with <tt>Tag</tt> = <a href="rc_binomial_heap_tag.html"><tt>rc_binomial_heap_tag</tt></a>
  91 </li>
  92 <li>
  93 binary_heap-
  94 <a href="priority_queue.html"><tt>priority_queue</tt></a>
  95  with <tt>Tag</tt> = <a href="binary_heap_tag.html"><tt>binary_heap_tag</tt></a>
  96 </li>
  97 <li>
  98 binomial_heap-
  99 <a href="priority_queue.html"><tt>priority_queue</tt></a>
 100  with <tt>Tag</tt> = <a href="binomial_heap_tag.html"><tt>binomial_heap_tag</tt></a>
 101 </li>
 102 <li>
 103 n_pq_vector-
 104 <tt>std::priority_queue</tt> adapting <tt>std::vector</tt></li>
 105 <li>
 106 pairing_heap-
 107 <a href="priority_queue.html"><tt>priority_queue</tt></a>
 108  with <tt>Tag</tt> = <a href="pairing_heap_tag.html"><tt>pairing_heap_tag</tt></a>
 109 </li>
 110 <li>
 111 thin_heap-
 112 <a href="priority_queue.html"><tt>priority_queue</tt></a>
 113  with <tt>Tag</tt> = <a href="thin_heap_tag.html"><tt>thin_heap_tag</tt></a>
 114 </li>
 115 </ol>
 116 </div><div style="width: 100%; height: 20px"></div></div>
 117 </div>
 118 </div>
 119 </div>
 120 </div>
 121 <div id="NPL_res_div">
 122 <div id="NPL_local">
 123 <div id="NPL_priority_queue_text_push_timing_test">
 124 <div id="NPL_pq">
 125 <div id="NPL_Native_and__tt_pb_ds_455tt__priority_queue__tt_push_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_text_push_timing_test_local.png" alt="no image" /></a></h6>NPL: Native and <tt>pb ds</tt> priority queue <tt>push</tt> timing test - <a href = "pq_performance_tests.html#local">local</a></div><div style = "width: 100%; height: 20px"></div></div>
 126 </div>
 127 </div>
 128 </div>
 129 </div>
 130 <div id="NBRG_res_div">
 131 <div id="NBRG_gcc">
 132 <div id="NBRG_pairing_priority_queue_text_push_timing_test">
 133 <div id="NBRG_pq">
 134 <div id="NBRG_Native_and__tt_pb_ds_455tt__pairing_priority_queue__tt_push_455tt__timing_test"><div style="border-style: dotted; border-width: 1px; border-color: lightgray"><h6 class="c1"><a name="NBRG" id="NBRG"><img src="pairing_priority_queue_text_push_timing_test_gcc.png" alt="no image" /></a></h6>NBRG: Native and <tt>pb ds</tt> pairing priority queue <tt>push</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>
 135 <ol>
 136 <li>
 137 n_pq_vector-
 138 <tt>std::priority_queue</tt> adapting <tt>std::vector</tt></li>
 139 <li>
 140 n_pq_deque-
 141 <tt>std::priority_queue</tt> adapting <tt>std::deque</tt></li>
 142 <li>
 143 thin_heap-
 144 <a href="priority_queue.html"><tt>priority_queue</tt></a>
 145  with <tt>Tag</tt> = <a href="thin_heap_tag.html"><tt>thin_heap_tag</tt></a>
 146 </li>
 147 <li>
 148 pairing_heap-
 149 <a href="priority_queue.html"><tt>priority_queue</tt></a>
 150  with <tt>Tag</tt> = <a href="pairing_heap_tag.html"><tt>pairing_heap_tag</tt></a>
 151 </li>
 152 </ol>
 153 </div><div style="width: 100%; height: 20px"></div></div>
 154 </div>
 155 </div>
 156 </div>
 157 </div>
 158 <div id="NBRM_res_div">
 159 <div id="NBRM_msvc">
 160 <div id="NBRM_pairing_priority_queue_text_push_timing_test">
 161 <div id="NBRM_pq">
 162 <div id="NBRM_Native_and__tt_pb_ds_455tt__pairing_priority_queue__tt_push_455tt__timing_test"><div style="border-style: dotted; border-width: 1px; border-color: lightgray"><h6 class="c1"><a name="NBRM" id="NBRM"><img src="pairing_priority_queue_text_push_timing_test_msvc.png" alt="no image" /></a></h6>NBRM: Native and <tt>pb ds</tt> pairing priority queue <tt>push</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>
 163 <ol>
 164 <li>
 165 n_pq_deque-
 166 <tt>std::priority_queue</tt> adapting <tt>std::deque</tt></li>
 167 <li>
 168 n_pq_vector-
 169 <tt>std::priority_queue</tt> adapting <tt>std::vector</tt></li>
 170 <li>
 171 pairing_heap-
 172 <a href="priority_queue.html"><tt>priority_queue</tt></a>
 173  with <tt>Tag</tt> = <a href="pairing_heap_tag.html"><tt>pairing_heap_tag</tt></a>
 174 </li>
 175 <li>
 176 thin_heap-
 177 <a href="priority_queue.html"><tt>priority_queue</tt></a>
 178  with <tt>Tag</tt> = <a href="thin_heap_tag.html"><tt>thin_heap_tag</tt></a>
 179 </li>
 180 </ol>
 181 </div><div style="width: 100%; height: 20px"></div></div>
 182 </div>
 183 </div>
 184 </div>
 185 </div>
 186 <div id="NBRL_res_div">
 187 <div id="NBRL_local">
 188 <div id="NBRL_pairing_priority_queue_text_push_timing_test">
 189 <div id="NBRL_pq">
 190 <div id="NBRL_Native_and__tt_pb_ds_455tt__pairing_priority_queue__tt_push_455tt__timing_test"><div style = "border-style: dotted; border-width: 1px; border-color: lightgray"><h6 class="c1"><a name="NBRL" id= "NBRL"><img src="pairing_priority_queue_text_push_timing_test_local.png" alt="no image" /></a></h6>NBRL: Native and <tt>pb ds</tt> pairing priority queue <tt>push</tt> timing test - <a href = "pq_performance_tests.html#local">local</a></div><div style = "width: 100%; height: 20px"></div></div>
 191 </div>
 192 </div>
 193 </div>
 194 </div>
 195 <h2><a name="observations" id="observations">Observations</a></h2>
 196 <p>Pairing heaps (<a href="priority_queue.html"><tt>priority_queue</tt></a> with
 197     <tt>Tag</tt> = <a href="pairing_heap_tag.html"><tt>pairing_heap_tag</tt></a>)
 198     are the most suited for sequences of <tt>push</tt> and
 199     <tt>pop</tt> operations of non-primitive types (<i>e.g.</i>
 200 <tt>std::string</tt>s). (see also <a href="priority_queue_text_push_pop_timing_test.html">Priority Queue
 201     Text <tt>push</tt> and <tt>pop</tt> Timing Test</a>.) They are
 202     less constrained than binomial heaps, <i>e.g.</i>, and since
 203     they are node-based, they outperform binary heaps. (See
 204     <a href="priority_queue_random_int_push_timing_test.html">Priority
 205     Queue Random Integer <tt>push</tt> Timing Test</a> for the case
 206     of primitive types.)</p>
 207 <p>The STL's priority queues do not seem to perform well in
 208     this case: the <tt>std::vector</tt> implementation needs to
 209     perform a logarithmic sequence of string operations for each
 210     operation, and the deque implementation is possibly hampered by
 211     its need to manipulate a relatively-complex type (deques
 212     support a <i>O(1)</i> <tt>push_front</tt>, even though it is
 213     not used by <tt>std::priority_queue</tt>.)</p>
 214 <p><a href="pq_performance_tests.html#pq_observations">Priority-Queue
 215     Performance Tests::Observations</a> discusses this further and
 216     summarizes.</p>
 217 </div>
 218 </body>
 219 </html>