Re: [SPAM?] Re: Asynchronous I/O Support

From: NikhilS <nikkhils(at)gmail(dot)com>
To: "Martijn van Oosterhout" <kleptog(at)svana(dot)org>
Cc: "Ron Mayer" <rm_pg(at)cheapcomplexdevices(dot)com>, "Zeugswetter Andreas ADI SD" <ZeugswetterA(at)spardat(dot)at>, pgsql-hackers(at)postgresql(dot)org
Subject: Re: [SPAM?] Re: Asynchronous I/O Support
Date: 2006-10-25 07:17:28
Message-ID: d3c4af540610250017o7b66880ahed1b10c7d8819a26@mail.gmail.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

Hi,

While we are at async i/o. I think direct i/o and concurrent i/o also
deserve a look at. The archives suggest that Bruce had some misgivings about
dio because of no kernel caching, but almost all databases seem to
(carefully) use dio (Solaris, Linux, ?) and cio (AIX) extensively nowadays.

Since these can be turned on a per file basis, perf testing them out should
be simpler too.

Regards,
Nikhils

On 10/25/06, Martijn van Oosterhout <kleptog(at)svana(dot)org> wrote:
>
> On Tue, Oct 24, 2006 at 12:53:23PM -0700, Ron Mayer wrote:
> > Anyway, for those who want to see what they do in Linux,
> > http://www.gelato.unsw.edu.au/lxr/source/mm/fadvise.c
> > Pretty scary that Bruce said it could make older linuxes
> > dump core - there isn't a lot of code there.
>
> The bug was probably in the glibc interface to the kernel. Google found
> this:
>
> http://sourceware.org/ml/libc-hacker/2004-03/msg00000.html
>
> i.e. posix_fadvise appears to have been broken on all 64-bit
> architechtures prior to March 2004 due to a silly linking error.
>
> And then things like this:
>
> http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=313219
>
> Which suggest that prior to glibc 2.3.5, posix_fadvise crashed on 2.4
> kernels. That's a fairly recent version, so the bug would still be
> fairly widespead.
>
> Have a nice day,
> --
> Martijn van Oosterhout <kleptog(at)svana(dot)org> http://svana.org/kleptog/
> > From each according to his ability. To each according to his ability to
> litigate.
>
>
> -----BEGIN PGP SIGNATURE-----
> Version: GnuPG v1.4.1 (GNU/Linux)
>
> iD8DBQFFPnYrIB7bNG8LQkwRAuAqAJ4uqx8y9LxUa9RcEDm7CPwZ2lkS2wCfYxjB
> 2KzJ7iDYU21lumcZT6cHeLI=
> =MzUY
> -----END PGP SIGNATURE-----
>
>
>

--
All the world's a stage, and most of us are desperately unrehearsed.

In response to

Browse pgsql-hackers by date

  From Date Subject
Next Message Hannu Krosing 2006-10-25 07:37:57 Re: Replication documentation addition
Previous Message Cesar Suga 2006-10-25 06:51:35 Re: [DOCS] Replication documentation addition