Re: Larry Ellison comments on Microsoft's benchmark

If you double the number of machines and disk, you have hot standby - performance doesn't change after a failure (12 machines sit idle in case any of the 12 doing real work fail - after the failure and transfer, you still have 12 machines handling the workload).

Mutual takeover uses machines doing other work to back each other up. After a failure, performance goes down (11 machines are doing work intended for 12 machines).

It's the standard tradeoff between price and performance. The math of whether a shared disk database is n times more reliable than a shared nothing database running on n nodes will be left as an exercise for the reader.

Ivana Humpalot wrote:

> ...

some text snipped

> ...The above appears to conflict with what you said earlier.
> (Following paragraph reproduced from your earlier post:)
>
> > The published benchmark does not include high availability machines or
> > Microsoft Cluster Server (MSCS). If you wanted to back up each machine,
> > you'd need hot standby machines (doubling the number of CPU's and RAM,
> > but not increasing the disk), mutual takeover machines running some other
> > workload, or have the machines back each other up (which is very common
> > for DB2 EEE customers).
>
> So first you said you have to double the number of CPU's and RAM.
> Now you appear to be advocating a different approach -- rather
> than doubling the CPU's and RAM, each node can be backed up in a
> mutual takeover configuration?
>
Received on Thu Jul 06 2000 - 00:00:00 CDT