Re: [3/4] kevent: AIO, aio_sendfile() implementation.

["Sébastien Dugué" <sebastien.dugue@bull.net>]

On Wed, 2006-07-26 at 09:22 -0700, Badari Pulavarty wrote:
> Ulrich Drepper wrote:
> > Christoph Hellwig wrote:
> >   
> >>> My personal opinion on existing AIO is that it is not the right design.
> >>> Benjamin LaHaise agree with me (if I understood him right),
> >>>       
> >> I completely agree with that aswell.
> >>     
> >
> > I agree, too, but the current code is not the last of the line.  Suparna
> > has a st of patches which make the current kernel aio code work much
> > better and especially make it really usable to implement POSIX AIO.
> >
> > In Ottawa we were talking about submitting it and Suparna will.  We just
> > thought about a little longer timeframe.  I guess it could be
> > accelerated since he mostly has the patch done.  But I don't know her
> > schedule.
> >
> > Important here is, don't base any decision on the current aio
> > implementation.
> >   
> Ulrich,
> 
> Suparna mentioned your interest in making POSIX glibc aio work with 
> kernel-aio at OLS.
> We thought taking a re-look at the (kernel side) work BULL did, would be 
> a nice starting
> point. I re-based those patches to 2.6.18-rc2 and sent it to Zach Brown 
> for review before
> sending them out to list.
> 
> These patches does NOT make AIO any cleaner. All they do is add 
> functionality to support
> POSIX AIO easier. These are
> 
> [ PATCH 1/3 ]  Adding signal notification for event completion
> 
> [ PATCH 2/3 ]  lio (listio) completion semantics
> 
> [ PATCH 3/3 ] cancel_fd support

  Badari,

  Thanks for refreshing those patches, they have been sitting here
for quite some time now and collected dust.

  I also think Suparna's patchset for doing buffered AIO would be
a real plus here.

> 
> Suparna explained these in the following article:
> 
> http://lwn.net/Articles/148755/
> 
> If you think, this is a reasonable direction/approach for the kernel and 
> you would take care
> of glibc side of things - I can spend time on these patches, getting 
> them to reasonable shape
> and push for inclusion.

  Ulrich, I you want to have a look at how those patches are put to
use in libposix-aio, have a look at http://sourceforge.net/projects/paiol.

  It could be a starting point for glibc.

  Thanks,

  Sébastien.

-- 
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  Sébastien Dugué                BULL/FREC:B1-247
  phone: (+33) 476 29 77 70      Bullcom: 229-7770

  mailto:sebastien.dugue@bull.net

  Linux POSIX AIO: http://www.bullopensource.org/posix
                   http://sourceforge.net/projects/paiol

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