Hello I running firebird 1.5.1 Classical Server on MDK 10.1

Dual 800 FSB 3.0 GHZ Xeon HT
2GB Ram
RAID 0+1 WITH 4 x 36GB 15K SCSI HDD.

I would like to optimize my firebird.conf
What should i change.
On more thing I work with 120MB database curently.
I run delete rows it need more than 4 hours to complete.
with only 22 % usage for all cpus.



My questions is what do i need to change in fibird.conf to speed up this.
Thank you.