Re: RAC versus simplistic load-balancing of replicated databases

Kevin Murphy wrote:

> Q: one person referred to a ram disk. This is interesting to me.
> When using a ramdisk, would you try to disable Oracle's buffering as
> much as possible? When would you use a ram disk as opposed to giving
> Oracle tons of buffer RAM?
>

(I wrote about the RAM disk ...)

My reference to RAM disk was purely based on the fact that the size of your DB is small enough to do so economically.

I do not advocate using RAM disk in this case, because you are using an Oracle environment. The SGA can be sized, and the in-memory constructs can be set to hold the same information as the disks, creating a RAM disk effect, without actually going to the effort of setting that up in the first place.

In your case, a properly tuned SGA & instance and judicious use of Read-only tablespaces should result in next-to-zero disk reads other than the initial query, so RAM disk should be useless.

In other words, totally in accordance with the implications of Sybrand's comment, I believe that tuning, especially at the application level, is by far the more significant way of ensuring your scalability requirement will be met.

(For the sake of argument - the place I'd consider RAM disk would be a well partitioned VLDB with extremely high performance update/insert requirements - create the partition in the RAM disk for the inserts and then use transportable tablespace capability to move the data to an analysis environment.) Received on Wed Jun 04 2003 - 20:57:09 CDT