[Twisted-Python] Recursive filescanning in Twisted??

[Jeff Bowden]

Jp Calderone wrote:

> Jeff Bowden wrote:
>
>> On Linux, file descriptors for disk files are always "ready".  
>
>
>   Right.
>
>> Since twisted is based on select() or poll() I'm guessing you will 
>> end up actually blocking on file reads.
>
>
>   Right.
>
>> I think you can get non-blocking file reads using the new AIO stuff 
>
>
>   On some systems, right.
>
>> but it's not really a good match for a single process server like 
>> twisted.
>
>
>   Hmm.  Why do you say this?  It's true that AIO will require reactor 
> support (IOCP is essentially such a reactor, except for Windows).  I 
> don't see a problem with using AIO in a single process, though, and 
> apparently neither did Pavel when he wrote IOCP.
>
>> I don't know about BSD/OSX or Windows.
>
>
>   KQueue supports on-disk files, I suspect.  There is no working 
> KQueue reactor, though, so that takes care of BSD/OSX.  Windows has IO 
> Completion Ports, which IOCP uses (hence the name ;).



I'm confused.  It sounds like you're saying that there is a reactor 
called IOCP that runs on Linux and uses AIO.  But it also sounds like 
it's Windows only.  Which?

Also, it occurred to me since I wrote my original response that I 
remember a while ago seeing support for async file i/o as a bullet item 
on the epoll TODO list.  I can't find any reference to it at the moment 
though.