title: Why is the Cold Miss Rate for a Cache Memory not affected by increasing or decreasing the capacity or associativity of the cache memory?
body: <p>Have a doubt about Compulsory/Cold misses for a Cache Memory.
  My knowledge about a compulsory miss is that <strong>It is the very first access to a block , independent of the cache size.</strong></p>
  
  <p>Cold Misses are affected by increasing/decreasing the block size. Here is my understanding, which seems to fit.</p>
  
  <pre><code>By increasing the block size, the number of blocks in the cache should 
  reduce, assuming the size of the cache is constant here. Therefore there
  would be decreased number of first time requests for each block. Hence the 
  cold miss should decrease.
  
  Correspondingly if the block size is decreased, the number of blocks would 
  increase, and hence the number of requets to access blocks for the first 
  time would also increase.
  </code></pre>
  
  <p>But I am not able to understand how it is <strong>Not Affected</strong> by Increasing or Decreasing the Cache Size OR Increasing/Decreasing the associativity of the cache !!</p>
  
  <pre><code>If the Cache Size increases, then the number of blocks also increase. So
  the cold misses should increases, as more number of empty blocks would
  be requested for the first time ???
  
  Similarly if the Cache Size is Decreased, the number of blocks would
  decrease which would have to be probed for the first time ??
  </code></pre>
  
  <p>My same doubt applies to increasing/decreasing the associativity as well.</p>
  
  <p>Looking for a better understanding of this.
  Help is greatly appreciated.</p>
  
  <p>Thanks,
  Ankit</p>