title: How to change kernel i/o buffer size
body: <p>I am running some experiments with I/O intensive applications and am trying to understand the effects of varying the kernel i/o buffer size, different elevator algorithms, and so on. </p>
  
  <p>How can I know the current size of the i/o buffer in the kernel? Does the kernel use more than one buffer as need arises? How can I change the size of this buffer? Is there a config file somewhere that stores this info?  </p>
  
  <p>(To be clear, I am not talking about processor or disk caches, I am talking about the buffer used by the kernel internally that buffers reads/writes before flushing them out to disk from time to time).</p>
  
  <p>Thanks in advance.</p>