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| <title>Hash Random Int Find Timing Test</title> |
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| <h1>Hash-Based Random-Integer <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 uniform i.i.d. |
| integer keys 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/random_int_find_timing.cc"><tt>random_int_find_timing_test</tt></a> |
| 200 200 2100)</p> |
| <h2><a name="purpose" id="purpose">Purpose</a></h2> |
| <p>The test checks the effect of different underlying |
| hash-tables (see <a href="hash_based_containers.html">Design::Associative |
| Containers::Associative Containers::Hash-Based Containers</a>), |
| range-hashing functions, and trigger policies (see <a href="hash_based_containers.html#hash_policies">Design::Associative |
| Containers::Hash-Based Containers::Hash Policies</a> and |
| <a href="hash_based_containers.html#resize_policies">Design::Associative |
| Containers::Hash-Based Containers::Resize Policies</a>).</p> |
| <h2><a name="results" id="results">Results</a></h2> |
| <p>Figures <a href="#NCCG">NCCG</a>, <a href="#NCCM">NCCM</a>, |
| and <a href="#NCCL">NCCL</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; Figures <a href="#NGPG">NGPG</a>, <a href="#NGPM">NGPM</a>, and <a href="#NGPL">NGPL</a> show the results |
| for the native and probing 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="NCCG_res_div"> |
| <div id="NCCG_gcc"> |
| <div id="NCCG_cc_hash_random_int_find_timing_test"> |
| <div id="NCCG_assoc"> |
| <div id="NCCG_Native_and_collision-chaining_hash_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="NCCG" id="NCCG"><img src="cc_hash_random_int_find_timing_test_gcc.png" alt="no image" /></a></h6>NCCG: Native and collision-chaining hash 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> |
| n_hash_map_ncah- |
| <tt>std::tr1::unordered_map</tt> with <tt>cache_hash_code</tt> = <tt><b>false</b></tt></li> |
| <li> |
| cc_hash_mod_prime_nea_lc_1div8_1div1_nsth_map- |
| <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_mod_prime_nea_lc_1div8_1div2_nsth_map- |
| <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>1/2</i></li> |
| <li> |
| cc_hash_mask_exp_nea_lc_1div8_1div1_nsth_map- |
| <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>1/1</i></li> |
| <li> |
| cc_hash_mask_exp_nea_lc_1div8_1div2_nsth_map- |
| <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="NCCM_res_div"> |
| <div id="NCCM_msvc"> |
| <div id="NCCM_cc_hash_random_int_find_timing_test"> |
| <div id="NCCM_assoc"> |
| <div id="NCCM_Native_and_collision-chaining_hash_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="NCCM" id="NCCM"><img src="cc_hash_random_int_find_timing_test_msvc.png" alt="no image" /></a></h6>NCCM: Native and collision-chaining hash 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> |
| cc_hash_mod_prime_nea_lc_1div8_1div1_nsth_map- |
| <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_mod_prime_nea_lc_1div8_1div2_nsth_map- |
| <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>1/2</i></li> |
| <li> |
| n_hash_map_ncah- |
| <tt>stdext::hash_map</tt></li> |
| <li> |
| cc_hash_mask_exp_nea_lc_1div8_1div1_nsth_map- |
| <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>1/1</i></li> |
| <li> |
| cc_hash_mask_exp_nea_lc_1div8_1div2_nsth_map- |
| <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="NCCL_res_div"> |
| <div id="NCCL_local"> |
| <div id="NCCL_cc_hash_random_int_find_timing_test"> |
| <div id="NCCL_assoc"> |
| <div id="NCCL_Native_and_collision-chaining_hash_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="NCCL" id= "NCCL"><img src="cc_hash_random_int_find_timing_test_local.png" alt="no image" /></a></h6>NCCL: Native and collision-chaining hash 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> |
| </div> |
| </div> |
| <div id="NGPG_res_div"> |
| <div id="NGPG_gcc"> |
| <div id="NGPG_gp_hash_random_int_find_timing_test"> |
| <div id="NGPG_assoc"> |
| <div id="NGPG_Native_and_collision-chaining_hash_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="NGPG" id="NGPG"><img src="gp_hash_random_int_find_timing_test_gcc.png" alt="no image" /></a></h6>NGPG: Native and collision-chaining hash 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> |
| gp_hash_mod_quadp_prime_nea_lc_1div8_1div2_nsth_map- |
| <a href="gp_hash_table.html"><tt>gp_hash_table</tt></a> |
| with <tt>Comb_Hash_Fn</tt> = <a href="direct_mod_range_hashing.html"><tt>direct_mod_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_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>1/2</i>, and <tt>Probe_Fn</tt> = <a href="quadratic_probe_fn.html"><tt>quadratic_probe_fn</tt></a> |
| </li> |
| <li> |
| n_hash_map_ncah- |
| <tt>std::tr1::unordered_map</tt> with <tt>cache_hash_code</tt> = <tt><b>false</b></tt></li> |
| <li> |
| gp_hash_mask_linp_exp_nea_lc_1div8_1div2_nsth_map- |
| <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> |
| </ol> |
| </div><div style="width: 100%; height: 20px"></div></div> |
| </div> |
| </div> |
| </div> |
| </div> |
| <div id="NGPM_res_div"> |
| <div id="NGPM_msvc"> |
| <div id="NGPM_gp_hash_random_int_find_timing_test"> |
| <div id="NGPM_assoc"> |
| <div id="NGPM_Native_and_collision-chaining_hash_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="NGPM" id="NGPM"><img src="gp_hash_random_int_find_timing_test_msvc.png" alt="no image" /></a></h6>NGPM: Native and collision-chaining hash 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> |
| gp_hash_mod_quadp_prime_nea_lc_1div8_1div2_nsth_map- |
| <a href="gp_hash_table.html"><tt>gp_hash_table</tt></a> |
| with <tt>Comb_Hash_Fn</tt> = <a href="direct_mod_range_hashing.html"><tt>direct_mod_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_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>1/2</i>, and <tt>Probe_Fn</tt> = <a href="quadratic_probe_fn.html"><tt>quadratic_probe_fn</tt></a> |
| </li> |
| <li> |
| n_hash_map_ncah- |
| <tt>stdext::hash_map</tt></li> |
| <li> |
| gp_hash_mask_linp_exp_nea_lc_1div8_1div2_nsth_map- |
| <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> |
| </ol> |
| </div><div style="width: 100%; height: 20px"></div></div> |
| </div> |
| </div> |
| </div> |
| </div> |
| <div id="NGPL_res_div"> |
| <div id="NGPL_local"> |
| <div id="NGPL_gp_hash_random_int_find_timing_test"> |
| <div id="NGPL_assoc"> |
| <div id="NGPL_Native_and_collision-chaining_hash_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="NGPL" id= "NGPL"><img src="gp_hash_random_int_find_timing_test_local.png" alt="no image" /></a></h6>NGPL: Native and collision-chaining hash 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> |
| </div> |
| </div> |
| <h2><a name="observations" id="observations">Observations</a></h2> |
| <p>In this setting, the choice of underlying hash-table (see |
| <a href="hash_based_containers.html">Design::Associative |
| Containers::Hash-Based Containers</a> ) affects performance |
| most, then the range-hashing scheme (See <a href="hash_based_containers.html#hash_policies">Design::Associative |
| Containers::Hash-Based Containers::Hash Policies</a> ), and, |
| only finally, other policies.</p> |
| <p>When comparing Figures <a href="#NCCG">NCCG</a> and <a href="#NCCM">NCCM</a> to <a href="#NGPG">NGPG</a> and <a href="#NGPM">NGPM</a> , respectively, it is apparent that the |
| probing containers are less efficient than the |
| collision-chaining containers (both |
| <tt>std::tr1::unordered_map</tt> and <tt>stdext::hash_map</tt> |
| use collision-chaining) in this case.</p> |
| <p>( <a href="hash_random_int_subscript_insert_timing_test.html">Hash-Based |
| Random-Integer Subscript Insert Timing Test</a> shows a |
| different case, where the situation is reversed; <a href="assoc_performance_tests.html#hash_based_types">Observations::Hash-Based |
| Container Types</a> discusses some further considerations.)</p> |
| <p>Within each type of hash-table, the range-hashing scheme |
| affects performance more than other policies; <a href="hash_text_find_find_timing_test.html#observations">Hash-Based |
| Text <tt>find</tt> Find Timing Test::Observations</a> discusses |
| this. In Figures <a href="#NCCG">NCCG</a> , <a href="#NCCM">NCCM</a> , <a href="#NGPG">NGPG</a> , and <a href="#NGPM">NGPM</a> , it should be noted that |
| <tt>std::tr1::unordered_map</tt> and <tt>stdext::hash_map</tt> |
| are hard-wired currently to mod-based and mask-based schemes, |
| respectively.</p> |
| <p><a href="assoc_performance_tests.html#hash_based_types">Observations::Hash-Based |
| Container Types</a> summarizes some observations on hash-based |
| containers; <a href="assoc_performance_tests.html#hash_based_policies">Observations::Hash-Based |
| Containers' Policies</a> summarizes some observations on |
| hash-based containers' policies.</p> |
| </div> |
| </body> |
| </html> |
