title: Locking and Redis
body: <p>We have 75 (and growing) servers that need to share data via Redis. All 75 servers would ideally want to write to two fields in Redis with <code>INCRBYFLOAT</code> operations. We anticipate eventually having potentially millions of daily write operations and <em>billions</em> of daily reads on these two fields. This data <strong>must</strong> be persistent.</p>
  
  <p>We're concerned that Redis locking might cause write operations to be repeatedly retried with many simultaneous attempts to increment the same field. </p>
  
  <p>Questions:</p>
  
  <ul>
  <li>Is multiple, simultaneous <code>INCRBYFLOAT</code> on a single field a bad idea under a very heavy load?</li>
  <li>Should we have an external process "summarize" separate fields and write the two fields instead? (this introduces another failure point)</li>
  <li>Will reads on those two fields block while writing?</li>
  </ul>