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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