Re: Asynchronous I/O Support

Hi,

"bgwriter doing aysncronous I/O for the dirty buffers that it is supposed to
sync"
Another decent use-case?

Regards,
Nikhils
EnterpriseDB   http://www.enterprisedb.com

On 10/15/06, Luke Lonergan <llonergan@greenplum.com> wrote:
>
> Martijn,
>
> On 10/15/06 10:56 AM, "Martijn van Oosterhout" <kleptog@svana.org> wrote:
>
> > Have enough systems actually got to the point of actually supporting
> > async I/O that it's worth implementing?
>
> I think there are enough high end applications / systems that need it at
> this point.
>
> The killer use-case we've identified is for the scattered I/O associated
> with index + heap scans in Postgres.  If we can issue ~5-15 I/Os in
> advance
> when the TIDs are widely separated it has the potential to increase the
> I/O
> speed by the number of disks in the tablespace being scanned.  At this
> point, that pattern will only use one disk.
>
> - Luke
>
>
>
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