OK I know the preferred method is to have a separate physical disk each for
the OS, log files, and database files. I'm curious what most people do in
the case of having two physical disks?

In my case I have the following layout:

RAID 1 drive --> Logical C: drive
--> Logical D: drive

RAID 5 drive --> Logical E: drive

The OS is on C ... now where to put the transaction and database files? Any
thoughts or experiences on the matter?

Thanks!

-Fred.

If I were stuck with that configuration I would put the logs on D: (or
C:), and the data files on E:. The reason is that writes to the logs
require that the process wait for the completion, while writes to the
data can happen "later" without waiting. And of course RAID 5 imposes
a major performance penalty to WRITE commands, taking something like
four times as much I/O. That breaks down to (1) read the parity disk,
(2) read the data disk that you are going to overwrite, (3) roll back
the data block out of the parity block, (4) roll the new data block
into the parity block, ((5) write the new parity data over the old,
and (6) write the new data over the old. Steps 1, 2, 5, and 6 are all
disk I/O.

Roy Harvey
Beacon Falls, CT

On Fri, 12 Sep 2008 16:17:30 -0400, "Fred Bulger" somewhere.com>
wrote:

Fred Bulger wrote: