On 18-Nov-05, at 1:07 AM, Luke Lonergan wrote:
> Greg,
>
>
> On 11/17/05 9:17 PM, "Greg Stark" <gsstark@mit.edu> wrote:
>
>> Ok, a more productive point: it's not really the size of the
>> database that
>> controls whether you're I/O bound or CPU bound. It's the available
>> I/O
>> bandwidth versus your CPU speed.
>
> Postgres + Any x86 CPU from 2.4GHz up to Opteron 280 is CPU bound
> after
> 110MB/s of I/O. This is true of Postgres 7.4, 8.0 and 8.1.
>
> A $1,000 system with one CPU and two SATA disks in a software RAID0
> will
> perform exactly the same as a $80,000 system with 8 dual core CPUs
> and the
> world's best SCSI RAID hardware on a large database for decision
> support
> (what the poster asked about).
Now there's an interesting line drawn in the sand. I presume you have
numbers to back this up ?
This should draw some interesting posts.
Dave
>
> Regards,
>
> - Luke
>
>
>
> ---------------------------(end of
> broadcast)---------------------------
> TIP 9: In versions below 8.0, the planner will ignore your desire to
> choose an index scan if your joining column's datatypes do not
> match
>