assets/Tracing-Tool.html-f5784e9c.js

import{_ as e,O as n,P as i,ah as s,aW as a}from"./framework-62ad666a.js";const t={},r=a(`<h2 id="查询性能追踪" tabindex="-1"><a class="header-anchor" href="#查询性能追踪" aria-hidden="true">#</a> 查询性能追踪</h2><p>IoTDB 支持使用 <code>TRACING</code> 关键词对查询语句进行性能追踪。用户可以使用性能追踪工具来分析语句执行中存在的潜在性能问题。</p><p>性能追踪的结果包括：</p><ol><li>查询执行过程中各个阶段的累积耗时。</li><li>与查询性能分析相关的统计信息，包括查询的时间序列数、涉及访问的 Tsfile 文件数、需要扫描的 chunk 总数以及平均每个 chunk 包含的数据点个数、读取的 Page 总数以及其中乱序 Page 的个数。</li></ol><p>例如执行 <code>tracing select * from root</code>，输出结果如下：</p><div class="language-text line-numbers-mode" data-ext="text"><pre class="language-text"><code>Tracing Activties:
+------------------------------------------------------+------------+
|                                              Activity|Elapsed Time|
+------------------------------------------------------+------------+
|Start to execute statement: tracing select * from root|           0|
|                            Parse SQL to physical plan|           4|
|                              Create and cache dataset|          16|
|                              * Num of series paths: 3|            |
|                       * Num of sequence files read: 2|            |
|                     * Num of unsequence files read: 1|            |
|        * Num of sequence chunks: 6, avg points: 100.0|            |
|      * Num of unsequence chunks: 3, avg points: 100.0|            |
|         * Num of Pages: 9, overlapped pages: 0 (0.0%)|            |
|                                      Request complete|          20|
+------------------------------------------------------+------------+
</code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div></div></div>`,6);function c(o,d){return n(),i("div",null,[s(`

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`),r])}const u=e(t,[["render",c],["__file","Tracing-Tool.html.vue"]]);export{u as default};