Re: Q for the standards gurus...
David Williams (djw@smooth1.demon.co.uk)
Wed, 30 Apr 1997 19:58:04 +0100
In message <Pine.LNX.3.91.970430105014.2851A-100000@toaster.roan.co.uk>,
Mike Jagdis <mike@roan.co.uk> writes
>I was thinking about AIO since some people say it absolutely
>essential for high end database engines. It looks relatively
>easy to do this in a very lightweight (i.e. no clone process)
>way - but only for directly accessed block devices. It's only
>when we have to go through the filesystem layers that we have
>to have a process context to do wait_on_buffers in or rewrite
>the filesystems.
>
> Question: I know wossisname, Gallmeister, gives AIO examples
>of AIO on ordinary files. I also know that SCO only does AIO
>on raw devices. What do other systems do? What is actually
>required by the standards? Would everyone or anyone be happy
>with AIO on block devices only?
Yes - Informix only uses KAIO aghainst raw devices anyway..
probably because it's only available on raw devices on most
platforms.
>
> Mike
>
--
David Williams