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diff --git a/gcc-4.4.3/libstdc++-v3/doc/html/ext/pb_ds/hash_random_int_erase_mem_usage_test.html b/gcc-4.4.3/libstdc++-v3/doc/html/ext/pb_ds/hash_random_int_erase_mem_usage_test.html new file mode 100644 index 000000000..2867595b0 --- /dev/null +++ b/gcc-4.4.3/libstdc++-v3/doc/html/ext/pb_ds/hash_random_int_erase_mem_usage_test.html @@ -0,0 +1,173 @@ +<!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 Locality of Reference Timing Test</title> +<meta http-equiv="Content-Type" content="text/html; charset=us-ascii" /> +</head> +<body> +<div id="page"> +<h1>Hash-Based Erase Memory-Use Test</h1> +<h2><a name="description" id="description">Description</a></h2> +<p>This test inserts a number of uniform i.i.d. integer keys + into a container, then erases all keys except one. It measures + the final size of the container.</p> +<p>(The test was executed with <a href="http://gcc.gnu.org/viewcvs/*checkout*/trunk/libstdc%2B%2B-v3/testsuite/performance/ext/pb_ds/hash_random_int_erase_mem_usage.cc"><tt>hash_random_int_erase_mem_usage.cc</tt></a> + 2000 2000 2100)</p> +<h2><a name="purpose" id="purpose">Purpose</a></h2> +<p>The test checks how containers adjust internally as their + logical size decreases (see <a href="motivation.html#assoc_ers_methods">Motivation::Associative + Containers::Slightly Different Methods::Methods Related to + Erase</a>).</p> +<h2><a name="results" id="results">Results</a></h2> +<p>Figures <a href="#NHG">NHG</a>, <a href="#NHM">NHM</a> and + <a href="#NHL">NHL</a> show the results for the native and + collision-chaining types in <a href="assoc_performance_tests.html#gcc"><u>g++</u></a>, <a href="assoc_performance_tests.html#msvc"><u>msvc++</u></a> and + <a href="assoc_performance_tests.html#local"><u>local</u></a>, + respectively.</p> +<div id="NHG_res_div"> +<div id="NHG_gcc"> +<div id="NHG_hash_random_int_erase_mem_usage_test"> +<div id="NHG_assoc"> +<div id="NHG_Native_456_collision-chaing_456_and_probing_456_hash_random_int_erase_test"><div style="border-style: dotted; border-width: 1px; border-color: lightgray"><h6 class="c1"><a name="NHG" id="NHG"><img src="hash_random_int_erase_mem_usage_test_gcc.png" alt="no image" /></a></h6>NHG: Native, collision-chaing, and probing, hash random int erase test - <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> +n_hash_set_ncah- +<tt>std::tr1::unordered_set</tt> with <tt>cache_hash_code</tt> = <tt><b>false</b></tt></li> +<li> +gp_hash_mask_linp_exp_nea_lc_1div8_1div2_nsth_set- +<a href="gp_hash_table.html"><tt>gp_hash_table</tt></a> + with <tt>Comb_Hash_Fn</tt> = <a href="direct_mask_range_hashing.html"><tt>direct_mask_range_hashing</tt></a> +, <tt>Resize_Policy</tt> = <a href="hash_standard_resize_policy.html"><tt>hash_standard_resize_policy</tt></a> + with <tt>Size_Policy</tt> = <a href="hash_exponential_size_policy.html"><tt>hash_exponential_size_policy</tt></a> +, and <tt>Trigger_Policy</tt> = <a href="hash_load_check_resize_trigger.html"><tt>hash_load_check_resize_trigger</tt></a> + with <i>α<sub>min</sub></i> = <i>1/8</i> and <i>α<sub>max</sub></i> = <i>1/2</i>, and <tt>Probe_Fn</tt> = <a href="linear_probe_fn.html"><tt>linear_probe_fn</tt></a> +</li> +<li> +cc_hash_mod_prime_nea_lc_1div8_1div1_nsth_set- +<a href="cc_hash_table.html"><tt>cc_hash_table</tt></a> +with <tt>Comb_Hash_Fn</tt> = <a href="direct_mod_range_hashing.html"><tt>direct_mod_range_hashing</tt></a> +, and <tt>Resize_Policy</tt> = <a href="hash_standard_resize_policy.html"><tt>hash_standard_resize_policy</tt></a> + with <tt>Size_Policy</tt> = <a href="hash_prime_size_policy.html"><tt>hash_prime_size_policy</tt></a> +, and <tt>Trigger_Policy</tt> = <a href="hash_load_check_resize_trigger.html"><tt>hash_load_check_resize_trigger</tt></a> + with <i>α<sub>min</sub></i> = <i>1/8</i> and <i>α<sub>max</sub></i> = <i>1/1</i></li> +<li> +cc_hash_mask_exp_nea_lc_1div8_1div2_nsth_set- +<a href="cc_hash_table.html"><tt>cc_hash_table</tt></a> +with <tt>Comb_Hash_Fn</tt> = <a href="direct_mask_range_hashing.html"><tt>direct_mask_range_hashing</tt></a> +, and <tt>Resize_Policy</tt> = <a href="hash_standard_resize_policy.html"><tt>hash_standard_resize_policy</tt></a> + with <tt>Size_Policy</tt> = <a href="hash_exponential_size_policy.html"><tt>hash_exponential_size_policy</tt></a> +, and <tt>Trigger_Policy</tt> = <a href="hash_load_check_resize_trigger.html"><tt>hash_load_check_resize_trigger</tt></a> + with <i>α<sub>min</sub></i> = <i>1/8</i> and <i>α<sub>max</sub></i> = <i>1/2</i></li> +</ol> +</div><div style="width: 100%; height: 20px"></div></div> +</div> +</div> +</div> +</div> +<div id="NHM_res_div"> +<div id="NHM_msvc"> +<div id="NHM_hash_random_int_erase_mem_usage_test"> +<div id="NHM_assoc"> +<div id="NHM_Native_456_collision-chaing_456_and_probing_456_hash_random_int_erase_test"><div style="border-style: dotted; border-width: 1px; border-color: lightgray"><h6 class="c1"><a name="NHM" id="NHM"><img src="hash_random_int_erase_mem_usage_test_msvc.png" alt="no image" /></a></h6>NHM: Native, collision-chaing, and probing, hash random int erase test - <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> +n_hash_set_ncah- +<tt>stdext::hash_set</tt></li> +<li> +gp_hash_mask_linp_exp_nea_lc_1div8_1div2_nsth_set- +<a href="gp_hash_table.html"><tt>gp_hash_table</tt></a> + with <tt>Comb_Hash_Fn</tt> = <a href="direct_mask_range_hashing.html"><tt>direct_mask_range_hashing</tt></a> +, <tt>Resize_Policy</tt> = <a href="hash_standard_resize_policy.html"><tt>hash_standard_resize_policy</tt></a> + with <tt>Size_Policy</tt> = <a href="hash_exponential_size_policy.html"><tt>hash_exponential_size_policy</tt></a> +, and <tt>Trigger_Policy</tt> = <a href="hash_load_check_resize_trigger.html"><tt>hash_load_check_resize_trigger</tt></a> + with <i>α<sub>min</sub></i> = <i>1/8</i> and <i>α<sub>max</sub></i> = <i>1/2</i>, and <tt>Probe_Fn</tt> = <a href="linear_probe_fn.html"><tt>linear_probe_fn</tt></a> +</li> +<li> +cc_hash_mod_prime_nea_lc_1div8_1div1_nsth_set- +<a href="cc_hash_table.html"><tt>cc_hash_table</tt></a> +with <tt>Comb_Hash_Fn</tt> = <a href="direct_mod_range_hashing.html"><tt>direct_mod_range_hashing</tt></a> +, and <tt>Resize_Policy</tt> = <a href="hash_standard_resize_policy.html"><tt>hash_standard_resize_policy</tt></a> + with <tt>Size_Policy</tt> = <a href="hash_prime_size_policy.html"><tt>hash_prime_size_policy</tt></a> +, and <tt>Trigger_Policy</tt> = <a href="hash_load_check_resize_trigger.html"><tt>hash_load_check_resize_trigger</tt></a> + with <i>α<sub>min</sub></i> = <i>1/8</i> and <i>α<sub>max</sub></i> = <i>1/1</i></li> +<li> +cc_hash_mask_exp_nea_lc_1div8_1div2_nsth_set- +<a href="cc_hash_table.html"><tt>cc_hash_table</tt></a> +with <tt>Comb_Hash_Fn</tt> = <a href="direct_mask_range_hashing.html"><tt>direct_mask_range_hashing</tt></a> +, and <tt>Resize_Policy</tt> = <a href="hash_standard_resize_policy.html"><tt>hash_standard_resize_policy</tt></a> + with <tt>Size_Policy</tt> = <a href="hash_exponential_size_policy.html"><tt>hash_exponential_size_policy</tt></a> +, and <tt>Trigger_Policy</tt> = <a href="hash_load_check_resize_trigger.html"><tt>hash_load_check_resize_trigger</tt></a> + with <i>α<sub>min</sub></i> = <i>1/8</i> and <i>α<sub>max</sub></i> = <i>1/2</i></li> +</ol> +</div><div style="width: 100%; height: 20px"></div></div> +</div> +</div> +</div> +</div> +<div id="NHM_res_div"> +<div id="NHM_msvc"> +<div id="NHM_hash_random_int_erase_mem_usage_test"> +<div id="NHM_assoc"> +<div id="NHM_Native_456_collision-chaing_456_and_probing_456_hash_random_int_erase_test"><div style="border-style: dotted; border-width: 1px; border-color: lightgray"><h6 class="c1"><a name="NHM" id="NHM"><img src="hash_random_int_erase_mem_usage_test_msvc.png" alt="no image" /></a></h6>NHM: Native, collision-chaing, and probing, hash random int erase test - <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> +n_hash_set_ncah- +<tt>stdext::hash_set</tt></li> +<li> +gp_hash_mask_linp_exp_nea_lc_1div8_1div2_nsth_set- +<a href="gp_hash_table.html"><tt>gp_hash_table</tt></a> + with <tt>Comb_Hash_Fn</tt> = <a href="direct_mask_range_hashing.html"><tt>direct_mask_range_hashing</tt></a> +, <tt>Resize_Policy</tt> = <a href="hash_standard_resize_policy.html"><tt>hash_standard_resize_policy</tt></a> + with <tt>Size_Policy</tt> = <a href="hash_exponential_size_policy.html"><tt>hash_exponential_size_policy</tt></a> +, and <tt>Trigger_Policy</tt> = <a href="hash_load_check_resize_trigger.html"><tt>hash_load_check_resize_trigger</tt></a> + with <i>α<sub>min</sub></i> = <i>1/8</i> and <i>α<sub>max</sub></i> = <i>1/2</i>, and <tt>Probe_Fn</tt> = <a href="linear_probe_fn.html"><tt>linear_probe_fn</tt></a> +</li> +<li> +cc_hash_mod_prime_nea_lc_1div8_1div1_nsth_set- +<a href="cc_hash_table.html"><tt>cc_hash_table</tt></a> +with <tt>Comb_Hash_Fn</tt> = <a href="direct_mod_range_hashing.html"><tt>direct_mod_range_hashing</tt></a> +, and <tt>Resize_Policy</tt> = <a href="hash_standard_resize_policy.html"><tt>hash_standard_resize_policy</tt></a> + with <tt>Size_Policy</tt> = <a href="hash_prime_size_policy.html"><tt>hash_prime_size_policy</tt></a> +, and <tt>Trigger_Policy</tt> = <a href="hash_load_check_resize_trigger.html"><tt>hash_load_check_resize_trigger</tt></a> + with <i>α<sub>min</sub></i> = <i>1/8</i> and <i>α<sub>max</sub></i> = <i>1/1</i></li> +<li> +cc_hash_mask_exp_nea_lc_1div8_1div2_nsth_set- +<a href="cc_hash_table.html"><tt>cc_hash_table</tt></a> +with <tt>Comb_Hash_Fn</tt> = <a href="direct_mask_range_hashing.html"><tt>direct_mask_range_hashing</tt></a> +, and <tt>Resize_Policy</tt> = <a href="hash_standard_resize_policy.html"><tt>hash_standard_resize_policy</tt></a> + with <tt>Size_Policy</tt> = <a href="hash_exponential_size_policy.html"><tt>hash_exponential_size_policy</tt></a> +, and <tt>Trigger_Policy</tt> = <a href="hash_load_check_resize_trigger.html"><tt>hash_load_check_resize_trigger</tt></a> + with <i>α<sub>min</sub></i> = <i>1/8</i> and <i>α<sub>max</sub></i> = <i>1/2</i></li> +</ol> +</div><div style="width: 100%; height: 20px"></div></div> +</div> +</div> +</div> +</div> +<div id="NHL_res_div"> +<div id="NHL_local"> +<div id="NHL_hash_random_int_erase_mem_usage_test"> +<div id="NHL_assoc"> +<div id="NHL_Native_456_collision-chaing_456_and_probing_456_hash_random_int_erase_test"><div style = "border-style: dotted; border-width: 1px; border-color: lightgray"><h6 class="c1"><a name="NHL" id= "NHL"><img src="hash_random_int_erase_mem_usage_test_local.png" alt="no image" /></a></h6>NHL: Native, collision-chaing, and probing, hash random int erase test - <a href = "assoc_performance_tests.html#local">local</a></div><div style = "width: 100%; height: 20px"></div></div> +</div> +</div> +</div> +</div> +<h2><a name="observations" id="observations">Observations</a></h2> +<p>STL hash-based containers act very differently than trees in + this respect. When erasing numerous keys from an STL + associative-container, the resulting memory user varies greatly + depending on whether the container is tree-based or hash-based. + As noted in <a href="motivation.html#assoc_methods">Motivation::Choice of + Methods</a> , this is a fundamental consequence of the STL's + associative containers' interface, it is not due to a specific + implementation.</p> +<p>(See <a href="priority_queue_text_pop_mem_usage_test.html">Priority Queue + Text <tt>pop</tt> Memory Use Test</a> for a similar phenomenon + regarding priority queues.)</p> +</div> +</body> +</html> |