Alan Bateman Alan.Bateman at Sun.COM
Thu Dec 31 08:40:56 PST 2009

John Davis wrote:
> Any plans to add the new 2008 Server API's to nio?
> GetQueuedCompletionStatusEx
Maybe, but it depends on the configuration. With a fixed thread pool 
then each thread retrieves a completion result and dispatches directly 
to the completion handler. For that case it would be inconvenient to 
retrieve completion results in batch. However for a cached or other 
thread pool then there are 1+ internal threads where each thread 
retrieves a completion result and submits a task to the thread pool to 
invoke the completion handler. For that configuration then it may be 
beneficial (esp. when there is a single internal thread retrieving 
events) but we would need to measure it before changing the code. Have 
you done any tests or  do you have performance results that you could 
share on this one?

> SetFileIoOverlappedRange
No specific plans at this point because it requires special privileges 
to lock pages into memory. However if there was some measurable 
improvement for privileged users then it wouldn't be too difficult to 
make of use of this as there is already a cache of OVERLAPPED structures 
per channel (or handle).

> SetFileCompletionNotificationModes
This one is new (to me anyway). In the implementation we don't use a 
completion events. If Windows is still setting some internal event and 
this can be skipped then it could be beneficial. We require a completion 
result per successful I/O operation so we couldn't use that mode.


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