Re: aio

Gerold Jury
2001-12-24T11:09:22Z

> On Friday 21 December 2001 14:48, Ingo Molnar wrote:
> > is this a fundamental limitation expressed in the interface, or just an
> > implementational limitation? On sockets this is indeed a big problem,
> > HTTP pipelining wants completely separate receive/send queues.
> >
> > Ingo
>

I got the _POSIX_SYNCHRONIZED_IO completely wrong.
It has nothing to do with the ordering of the aio read/write requests.

Aio_read and aio_write work with absolute positions inside the file size.
The order of requests is unspecified in SUSV V2.
SUSV V2 does neither prevent nor force the desired behaviour.

It seems like it is up to the implementation how to deal with the request
order.
As mentioned earlier, SGI-kaio does the right thing with the same interface.

I want to add, that a combination of sigwaitinfo / sigtimedwait and aio is a
very efficient way to deal with sockets. The accept may be handled with real
time signals as well by using fcntl F_SETSIG and F_SETFL FASYNC.

Gerold