Re: How to improve db performance with $7K?

> platter compared to the rotational speed, which would agree with the
> fact that you can read 70MB/sec, but it takes up to 13ms to seek.

    Actually :
    - the head has to be moved
    this time depends on the distance, for instance moving from a cylinder to
the next is very fast (it needs to, to get good throughput)
    - then you have to wait for the disk to spin until the information you
want comes in front of the head... statistically you have to wait a half
rotation. And this does not depend on the distance between the cylinders,
it depends on the position of the data in the cylinder.
    The more RPMs you have, the less you wait, which is why faster RPMs
drives have faster seek (they must also have faster actuators to move the
head)...