1<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" 2 "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 3 4<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> 5<head> 6<meta name="generator" content="HTML Tidy for Linux/x86 (vers 12 April 2005), see www.w3.org" /> 7<title>Priority Queue Random Int Push Pop Timing Test</title> 8<meta http-equiv="Content-Type" content="text/html; charset=us-ascii" /> 9</head> 10<body> 11<div id="page"> 12<h1>Priority Queue Random Integer <tt>push</tt> and 13 <tt>pop</tt> Timing Test</h1> 14<h2><a name="description" id="description">Description</a></h2> 15<p>This test inserts a number of values with i.i.d. integer 16 keys into a container using <tt>push</tt> , then removes them 17 using <tt>pop</tt> . It measures the average time for 18 <tt>push</tt> and <tt>pop</tt> as a function of the number of 19 values.</p> 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<tt>priority_queue_random_int_push_pop_timing_test</tt></a> 22 thirty_years_among_the_dead_preproc.txt 200 200 2100)</p> 23<h2><a name="purpose" id="purpose">Purpose</a></h2> 24<p>The test checks the effect of different underlying 25 data structures (see <a href="pq_design.html#pq_imp">Design::Priority 26 Queues::Implementations</a>).</p> 27<h2><a name="results" id="results">Results</a></h2> 28<p>Figures <a href="#NPG">NPG</a>, <a href="#NPM">NPM</a>, and 29 <a href="#NPL">NPL</a> shows the results for the native 30 priority queues and <tt>pb_ds</tt> 's priority queues in 31 <a href="pq_performance_tests.html#gcc"><u>g++</u></a>, 32 <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_random_int_push_pop_timing_test"> 38<div id="NPG_pq"> 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<ol> 41<li> 42thin_heap- 43<a href="priority_queue.html"><tt>priority_queue</tt></a> 44 with <tt>Tag</tt> = <a href="thin_heap_tag.html"><tt>thin_heap_tag</tt></a> 45</li> 46<li> 47rc_binomial_heap- 48<a href="priority_queue.html"><tt>priority_queue</tt></a> 49 with <tt>Tag</tt> = <a href="rc_binomial_heap_tag.html"><tt>rc_binomial_heap_tag</tt></a> 50</li> 51<li> 52binomial_heap- 53<a href="priority_queue.html"><tt>priority_queue</tt></a> 54 with <tt>Tag</tt> = <a href="binomial_heap_tag.html"><tt>binomial_heap_tag</tt></a> 55</li> 56<li> 57pairing_heap- 58<a href="priority_queue.html"><tt>priority_queue</tt></a> 59 with <tt>Tag</tt> = <a href="pairing_heap_tag.html"><tt>pairing_heap_tag</tt></a> 60</li> 61<li> 62n_pq_deque- 63<tt>std::priority_queue</tt> adapting <tt>std::deque</tt></li> 64<li> 65n_pq_vector- 66<tt>std::priority_queue</tt> adapting <tt>std::vector</tt></li> 67<li> 68binary_heap- 69<a href="priority_queue.html"><tt>priority_queue</tt></a> 70 with <tt>Tag</tt> = <a href="binary_heap_tag.html"><tt>binary_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_random_int_push_pop_timing_test"> 81<div id="NPM_pq"> 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<ol> 84<li> 85thin_heap- 86<a href="priority_queue.html"><tt>priority_queue</tt></a> 87 with <tt>Tag</tt> = <a href="thin_heap_tag.html"><tt>thin_heap_tag</tt></a> 88</li> 89<li> 90rc_binomial_heap- 91<a href="priority_queue.html"><tt>priority_queue</tt></a> 92 with <tt>Tag</tt> = <a href="rc_binomial_heap_tag.html"><tt>rc_binomial_heap_tag</tt></a> 93</li> 94<li> 95binomial_heap- 96<a href="priority_queue.html"><tt>priority_queue</tt></a> 97 with <tt>Tag</tt> = <a href="binomial_heap_tag.html"><tt>binomial_heap_tag</tt></a> 98</li> 99<li> 100pairing_heap- 101<a href="priority_queue.html"><tt>priority_queue</tt></a> 102 with <tt>Tag</tt> = <a href="pairing_heap_tag.html"><tt>pairing_heap_tag</tt></a> 103</li> 104<li> 105n_pq_deque- 106<tt>std::priority_queue</tt> adapting <tt>std::deque</tt></li> 107<li> 108n_pq_vector- 109<tt>std::priority_queue</tt> adapting <tt>std::vector</tt></li> 110<li> 111binary_heap- 112<a href="priority_queue.html"><tt>priority_queue</tt></a> 113 with <tt>Tag</tt> = <a href="binary_heap_tag.html"><tt>binary_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_random_int_push_pop_timing_test"> 124<div id="NPL_pq"> 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</div> 127</div> 128</div> 129</div> 130<h2><a name="observations" id="observations">Observations</a></h2> 131<p>Binary heaps are the most suited for sequences of 132 <tt>push</tt> and <tt>pop</tt> operations of primitive types 133 (<i>e.g.</i> <tt><b>int</b></tt>s). This is explained in 134 <a href="priority_queue_random_int_push_timing_test.html">Priority 135 Queue Random Int <tt>push</tt> Timing Test</a> . (See <a href="priority_queue_text_push_pop_timing_test.html">Priority Queue 136 Text <tt>push</tt> Timing Test</a> for the case of primitive 137 types.)</p> 138<p>At first glance it seems that the STL's vector-based 139 priority queue is approximately on par with <tt>pb_ds</tt>'s 140 corresponding priority queue. There are two differences 141 however:</p> 142<ol> 143<li>The STL's priority queue does not downsize the underlying 144 vector (or deque) as the priority queue becomes smaller 145 (see <a href="priority_queue_text_pop_mem_usage_test.html">Priority Queue 146 Text <tt>pop</tt> Memory Use Test</a>). It is therefore 147 gaining some speed at the expense of space.</li> 148<li>From <a href="priority_queue_random_int_push_pop_timing_test.html">Priority 149 Queue Random Integer <tt>push</tt> and <tt>pop</tt> Timing 150 Test</a>, it seems that the STL's priority queue is slower in 151 terms of <tt>pus</tt> operations. Since the number of 152 <tt>pop</tt> operations is at most that of <tt>push</tt> 153 operations, the test here is the "best" for the STL's 154 priority queue.</li> 155</ol> 156<p><a href="pq_performance_tests.html#pq_observations">Priority-Queue 157 Performance Tests::Observations</a> discusses this further and 158 summarizes.</p> 159</div> 160</body> 161</html> 162