title: Use MongoDB Allocation strategy effectively
body: <p>I am new to some of the MongoDB concepts like Allocation strategy. Currently I am using MongoDB-3.2.2 version, I am using the 
  same version with Windows-32 bit and 64 bit as well. As per the Mongo documents the default allocation strategy is "PowerOf2Sizes"
   and which is better for insert/update/delete operations. I have the follwing requirement:
  I am storing my logs into an array as one document. So Initially I started inserting one log into the array and then onwards I will update the
  same array in the document with no.of log entries. So I am inserting and updating the array in the document.
  Here I am using 32 bit (MMAPV1) and 64-bit(Wired Tiger) Engine.</p>
  
  <p>As per my understanding from the Mongo documents, I do not need to set any padding factor(through Allocation strategy) to 64 bit to avoid document movement.
  I only need to set padding factor(through allocation strategy) for 32 bit(MMAP v1 storage engine).</p>
  
  <p>Could any body tell me how can I use Allocation strategy for my above requirement? Or Is my Understanding correct?</p>