Greg,
On 11/17/05 9:17 PM, "Greg Stark" <gsstark@xxxxxxx> 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).
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
