title: Performance of Windows timer functions
body: <p>I trying to call a watchdog function every 500ms using <code>timeSetEvent</code>.</p>
  
  <p>Normally the watchdog is called without any problems. However when a DVD is inserted into a drive I don't get a callback for up to 8 secs as the system is busy reading the disk. Using <code>WindowsQueue</code> timer things aren't quite so bad and I get a 4 second day.</p>
  
  <p>My last attempt was to set thread priority to time critical and then sleep for 500ms, but again the callback didn't occur for 8secs.</p>
  
  <p>I am still running XP, but I'm not aware of changes made in later operating systems which would make this better.</p>
  
  <p>I am using the DVD insertion as an example. I'd like the code to be robust to other conditions if possible.</p>
  
  <p>Any suggestions greatly appreciated.</p>