Re: KITTEN: IETF 75 - 76

[Michael B Allen <miallen at ioplex.com>]

On Tue, 1 Sep 2009 22:21:57 -0700
Love Hörnquist Åstrand <lha at kth.se> wrote:

> 
> 1 sep 2009 kl. 18:40 skrev Michael B Allen:
> 
> > But the caller now knows that the function needs to be called again  
> > to complete the operation.
> 
> so consumer got to poll the library, that is no got from the  
> performance view.

Actually now that I think about it I only use the NOWAIT flag technique for client oriented routines. For example, if you wanted to perform 10 HTTP requests in parallel, you could use the NOWAIT flag to initiate the requests and then not use NOWAIT when collecting the responses.

If someone wanted to use async for an event loop (a single thread / process handling an arbitrary number of contexts concurrently) then the NOWAIT flag technique by itself would indeed require polling and would be inefficient.

However, if the caller had access to the underlying polling routine (like through a "gss_process_events" function that called select or whatever), then the caller could know if the status of *any* operation had changed and thus polling would not be required. The benefit of doing this would be that a single thread / process could be used to do everything.

Mike

-- 
Michael B Allen
Java Active Directory Integration
http://www.ioplex.com/