Spark Core快速入门系列(2) | Spark对集合的切片原理

逃离我推掉我的手 2022-11-27 15:38 147阅读 0赞

**`话不多说，直接看源码！`**  
ctrl+左键  
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**`这里就是讲怎么计算分区的`**  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQ2NTQ4ODU1_size_16_color_FFFFFF_t_70_pic_center 2]  
**`接下来就举个例子吧！`**  
(30,40,50,60,70,10,20,60,90,10) 数组有10个,切片为3

<table> 
 <thead> 
  <tr> 
   <th>start</th> 
   <th>end</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>0*10/3=0</td> 
   <td>(0+1)/10*3=3</td> 
  </tr> 
  <tr> 
   <td>1*10/3=3</td> 
   <td>(1+1)*10/3=6</td> 
  </tr> 
  <tr> 
   <td>2*10/3=6</td> 
   <td>(2+1)*10/3=10</td> 
  </tr> 
 </tbody> 
</table>

那么1分区有3个 2分区有3个 3分区有4个  
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