https://brian-hsu.github.io/tags/perf_counter_ns/Recent content in Perf_counter_ns on 布萊恩 | QA job | TestingHugozh-twThu, 17 Jun 2021 12:41:00 +0800https://brian-hsu.github.io/blog/my_share-023/Thu, 17 Jun 2021 12:41:00 +0800https://brian-hsu.github.io/blog/my_share-023/<h4 id="有時候用秒數計算執行時間">有時候用秒數計算執行時間</h4> <h4 id="測試資料不夠龐大的情況會使結果變成負值">測試資料不夠龐大的情況會使結果變成負值</h4> <h4 id="這時候使用奈秒來看會比較快一些">這時候使用奈秒來看會比較快一些</h4> <h4 id="1秒1000000000-ns-1ns-11000000000s">1秒=1000000000 (ns), 1(ns) =1／1000000000(s)；</h4> <h4 id="來看看-exsample-比較-deque-與-list-的-append-時間花費">來看看 exsample (比較 deque 與 list 的 append 時間花費)</h4> <div class="highlight"><pre tabindex="0" style="color:#586e75;background-color:#eee8d5;-moz-tab-size:4;-o-tab-size:4;tab-size:4;-webkit-text-size-adjust:none;"><code class="language-python" data-lang="python"><span style="display:flex;"><span><span style="color:#dc322f;font-weight:bold">from</span> <span style="color:#268bd2">collections</span> <span style="color:#dc322f;font-weight:bold">import</span> <span style="color:#268bd2">deque</span> </span></span><span style="display:flex;"><span><span style="color:#dc322f;font-weight:bold">import</span> <span style="color:#268bd2">time</span> </span></span><span style="display:flex;"><span> </span></span><span style="display:flex;"><span><span style="color:#268bd2">d</span> = <span style="color:#268bd2">deque</span>(<span style="color:#cb4b16">range</span>(<span style="color:#2aa198;font-weight:bold">10000000</span>)) </span></span><span style="display:flex;"><span><span style="color:#268bd2">l</span> = <span style="color:#cb4b16">list</span>(<span style="color:#cb4b16">range</span>(<span style="color:#2aa198;font-weight:bold">10000000</span>)) </span></span><span style="display:flex;"><span> </span></span><span style="display:flex;"><span><span style="color:#268bd2">t1</span> = <span style="color:#268bd2">time</span>.<span style="color:#268bd2">perf_counter_ns</span>() </span></span><span style="display:flex;"><span> </span></span><span style="display:flex;"><span><span style="color:#268bd2">d</span>.<span style="color:#268bd2">append</span>(-<span style="color:#2aa198;font-weight:bold">1</span>) </span></span><span style="display:flex;"><span><span style="color:#cb4b16">print</span>(<span style="color:#2aa198">&#39;deque Spend time(ns):&#39;</span>, <span style="color:#268bd2">time</span>.<span style="color:#268bd2">perf_counter_ns</span>() - <span style="color:#268bd2">t1</span>) </span></span><span style="display:flex;"><span> </span></span><span style="display:flex;"><span><span style="color:#268bd2">t2</span> = <span style="color:#268bd2">time</span>.<span style="color:#268bd2">perf_counter_ns</span>() </span></span><span style="display:flex;"><span> </span></span><span style="display:flex;"><span><span style="color:#268bd2">l</span>.<span style="color:#268bd2">append</span>(-<span style="color:#2aa198;font-weight:bold">1</span>) </span></span><span style="display:flex;"><span><span style="color:#cb4b16">print</span>(<span style="color:#2aa198">&#39;list Spend time(ns):&#39;</span>, <span style="color:#268bd2">time</span>.<span style="color:#268bd2">perf_counter_ns</span>() - <span style="color:#268bd2">t2</span>) </span></span></code></pre></div><h4 id="執行後顯示">執行後顯示</h4> <div class="highlight"><pre tabindex="0" style="color:#586e75;background-color:#eee8d5;-moz-tab-size:4;-o-tab-size:4;tab-size:4;-webkit-text-size-adjust:none;"><code class="language-shell" data-lang="shell"><span style="display:flex;"><span>deque Spend time(ns): <span style="color:#2aa198;font-weight:bold">4100</span> </span></span><span style="display:flex;"><span>list Spend time(ns): <span style="color:#2aa198;font-weight:bold">60945300</span> </span></span></code></pre></div><h4 id="用奈秒來看-可以清楚知道差距">用奈秒來看 可以清楚知道差距</h4> <h4 id="數值越大-花費時間越久">數值越大 花費時間越久</h4>