title: Saving and loading pkl files
body: <p>I'm using pkl files to save steps of a data analysis I'm doing. Basically in each step (which is also a .py file) I load a pkl file from the previous step and I save the result in a new pkl.</p>
  
  <p>In my last step the loading process it is suspiciously slow, especially if compared with the time the same computer uses to process the informations and creating the file... I'm just looking for some hint to understand what's going on.</p>
  
  <p>My suspects falls in the way I store the informations in the file: I create a big dictionary with all inside. So in the last case I have two dictionaries (of numbers) A and B, an array C and two dictionaries (of DataFrames) D and E; what I save as pkl is</p>
  
  <pre><code>dict_to_save={'A':A, 'B':B, 'C':C, 'D':D, 'E':E}
  </code></pre>
  
  <p>The reason of the suspect is that the pkl files of previous steps are larger files but their dictionaries have less keys (or less complex data type inside) and are loaded a way faster.</p>