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diff --git a/libstdc++-v3/doc/html/ext/pb_ds/tree_random_int_find_find_timing_test.html b/libstdc++-v3/doc/html/ext/pb_ds/tree_random_int_find_find_timing_test.html new file mode 100644 index 00000000000..9317cfc948d --- /dev/null +++ b/libstdc++-v3/doc/html/ext/pb_ds/tree_random_int_find_find_timing_test.html @@ -0,0 +1,160 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" + "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> + +<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> +<head> +<meta name="generator" content="HTML Tidy for Linux/x86 (vers 12 April 2005), see www.w3.org" /> +<title>Tree Text Find Timing Test</title> +<meta http-equiv="Content-Type" content="text/html; charset=us-ascii" /> +</head> +<body> +<div id="page"> +<h1>Tree-Based and Trie-Based Text <tt>find</tt> Find Timing + Test</h1> +<h2><a name="description" id="description">Description</a></h2> +<p>This test inserts a number of values with keys from an + arbitrary text ([<a href="references.html#wickland96thirty">wickland96thirty</a>]) into + a container, then performs a series of finds using + <tt>find</tt>. It measures the average time for <tt>find</tt> + as a function of the number of values inserted.</p> +<p>(The test was executed with <a href="../../../../testsuite/performance/ext/pb_ds/text_find_timing.cc"><tt>text_find_timing_test</tt></a> + thirty_years_among_the_dead_preproc.txt 200 200 2100)</p> +<h2><a name="purpose" id="purpose">Purpose</a></h2> +<p>The test checks the effect of different underlying + data structures.</p> +<h2><a name="results" id="results">Results</a></h2> +<p>Figures <a href="#NTTG">NTTG</a>, <a href="#NTTM">NTTM</a>, + and <a href="#NTTG">NTTL</a> show the results for the native, + tree-based, and trie-based types in <a href="assoc_performance_tests.html#gcc"><u>g++</u></a>, <a href="assoc_performance_tests.html#local"><u>local</u></a>, and + <a href="assoc_performance_tests.html#local"><u>local</u></a>, + respectively.</p> +<div id="NTTG_res_div"> +<div id="NTTG_gcc"> +<div id="NTTG_random_int_find_find_timing_test_tree"> +<div id="NTTG_assoc"> +<div id="NTTG_Native_456_tree-based_456_random_int_find_timing_test_using__tt_find_455tt_"><div style="border-style: dotted; border-width: 1px; border-color: lightgray"><h6 class="c1"><a name="NTTG" id="NTTG"><img src="random_int_find_find_timing_test_tree_gcc.png" alt="no image" /></a></h6>NTTG: Native, tree-based, random int find timing test using <tt>find</tt> - <a href="assoc_performance_tests.html#gcc">g++</a><p>In the above figure, the names in the legends have the following meaning:</p> +<ol> +<li> +splay_tree_map- +<a href="tree.html"><tt>tree</tt></a> + with <tt>Tag</tt> = <a href="splay_tree_tag.html"><tt>splay_tree_tag</tt></a> +, and <tt>Node_Update</tt> = <a href="null_tree_node_update.html"><tt>null_tree_node_update</tt></a> +</li> +<li> +ov_tree_map- +<a href="tree.html"><tt>tree</tt></a> + with <tt>Tag</tt> = <a href="ov_tree_tag.html"><tt>ov_tree_tag</tt></a> +, and <tt>Node_Update</tt> = <a href="null_tree_node_update.html"><tt>null_tree_node_update</tt></a> +</li> +<li> +n_map- +<tt>std::map</tt></li> +<li> +rb_tree_map- +<a href="tree.html"><tt>tree</tt></a> + with <tt>Tag</tt> = <a href="rb_tree_tag.html"><tt>rb_tree_tag</tt></a> +, and <tt>Node_Update</tt> = <a href="null_tree_node_update.html"><tt>null_tree_node_update</tt></a> +</li> +</ol> +</div><div style="width: 100%; height: 20px"></div></div> +</div> +</div> +<div id="NTTM_res_div"> +<div id="NTTM_msvc"> +<div id="NTTM_random_int_find_find_timing_test_tree"> +<div id="NTTM_assoc"> +<div id="NTTM_Native_456_tree-based_456_random_int_find_timing_test_using__tt_find_455tt_"><div style="border-style: dotted; border-width: 1px; border-color: lightgray"><h6 class="c1"><a name="NTTM" id="NTTM"><img src="random_int_find_find_timing_test_tree_msvc.png" alt="no image" /></a></h6>NTTM: Native, tree-based, random int find timing test using <tt>find</tt> - <a href="assoc_performance_tests.html#msvc">msvc++</a><p>In the above figure, the names in the legends have the following meaning:</p> +<ol> +<li> +splay_tree_map- +<a href="tree.html"><tt>tree</tt></a> + with <tt>Tag</tt> = <a href="splay_tree_tag.html"><tt>splay_tree_tag</tt></a> +, and <tt>Node_Update</tt> = <a href="null_tree_node_update.html"><tt>null_tree_node_update</tt></a> +</li> +<li> +ov_tree_map- +<a href="tree.html"><tt>tree</tt></a> + with <tt>Tag</tt> = <a href="ov_tree_tag.html"><tt>ov_tree_tag</tt></a> +, and <tt>Node_Update</tt> = <a href="null_tree_node_update.html"><tt>null_tree_node_update</tt></a> +</li> +<li> +n_map- +<tt>std::map</tt></li> +<li> +rb_tree_map- +<a href="tree.html"><tt>tree</tt></a> + with <tt>Tag</tt> = <a href="rb_tree_tag.html"><tt>rb_tree_tag</tt></a> +, and <tt>Node_Update</tt> = <a href="null_tree_node_update.html"><tt>null_tree_node_update</tt></a> +</li> +</ol> +</div><div style="width: 100%; height: 20px"></div></div> +</div> +</div> +<div id="NTTL_res_div"> +<div id="NTTL_local"> +<div id="NTTL_random_int_find_find_timing_test_tree"> +<div id="NTTL_assoc"> +<div id="NTTL_Native_456_tree-based_456_random_int_find_timing_test_using__tt_find_455tt_"><div style = "border-style: dotted; border-width: 1px; border-color: lightgray"><h6 class="c1"><a name="NTTL" id= "NTTL"><img src="random_int_find_find_timing_test_tree_local.png" alt="no image" /></a></h6>NTTL: Native, tree-based, random int find timing test using <tt>find</tt> - <a href = "assoc_performance_tests.html#local">local</a></div><div style = "width: 100%; height: 20px"></div></div> +</div> +</div> +<h2><a name="observations" id="observations">Observations</a></h2> +<p>For this setting, a splay tree (<a href="tree.html"><tt>tree</tt></a> + with <tt>Tag =</tt> <a href="splay_tree_tag.html"><tt>splay_tree_tag</tt></a>) + does not do well. This is possibly due to two + reasons:</p> +<ol> +<li>A splay tree is not guaranteed to be balanced + [<a href="references.html#motwani95random">motwani95random</a>]. + If a splay tree contains <i>n</i> nodes, its + average root-leaf path can be <i>m >> + log(n)</i>.</li> +<li>Assume a specific root-leaf search path has + length <i>m</i>, and the search-target node has + distance <i>m'</i> from the root. A red-black + tree will require <i>m + 1</i> comparisons to + find the required node; a splay tree will require + <i>2 m'</i> comparisons. A splay tree, + consequently, can perform many more comparisons + than a red-black tree.</li> +</ol> +<p>An ordered-vector tree (<a href="tree.html"><tt>tree</tt></a> + with <tt>Tag =</tt> <a href="ov_tree_tag.html"><tt>ov_tree_tag</tt></a>), + a red-black tree (<a href="tree.html"><tt>tree</tt></a> + with <tt>Tag =</tt> <a href="splay_tree_tag.html"><tt>rb_tree_tag</tt></a>), + and the native red-black tree all share + approximately the same performance.</p> +<p>An ordered-vector tree is slightly slower than + red-black trees, since it requires, in order to + find a key, more math operations than they do. + Conversely, an ordered-vector tree requires far + lower space than the others. ([<a href="references.html#austern00noset">austern00noset</a>], + however, seems to have an implementation that is + also faster than a red-black tree).</p> +<p>A PATRICIA trie (<a href="trie.html"><tt>trie</tt></a> + with <tt>Tag =</tt> <a href="pat_trie_tag.html"><tt>pat_trie_tag</tt></a>) + has good look-up performance, due to its large + fan-out in this case. In this setting, a PATRICIA + trie has lookup performance comparable to a hash + table (see <a href="hash_text_find_find_timing_test.html">Hash-Based + Text <tt>find</tt> Find Timing Test</a>), but it is + order preserving. This is not that surprising, + since a large fan-out PATRICIA trie works like a + hash table with collisions resolved by a sub-trie. + A large fan-out PATRICIA trie does not do well on + modifications (see <a href="tree_text_insert_timing_test.html">Tree-Based and + Trie-Based Text Insert Timing Test</a>). It is + possibly beneficial to semi-static settings, + therefore.</p> +<p><a href="assoc_performance_tests.html#tree_like_based_types"> + Observations::Tree-Like-Based Container Types</a> + summarizes some observations on tree-based and + trie-based containers.</p> +</div> +</div> +</div> +</div> +</div> +</div> +</div> +</body> +</html> |