title: memory limits and application pool recycle
body: <p>my web applications app pool configuration is 
  PeriodicRestartMemory : 512000
  PeriodicRestartPrivateMemory : 196608</p>
  
  <p>although the virtual memory limit is higher than private memory, app pool is recycled with virtual memory limits exceeded errors in the event log (instead of private memory).</p>
  
  <p>what is the reason for this? how could it exceed virtual memory limits before exceeding private memory limits? it seems that systems other allocations in virtual memory cause limits exceeded before applications private allocations exceed the limits, but what are those allocations of the system? or what is the root cause of this.</p>
  
  <p>thanks</p>