From: Lukas Beeler
Be aware that i did never say that my laptop would be more stable
or more resilient than a Power system in the specific configuration
in my mail - i just said it would PERFORM better.
Please forgive me, but the analogy of your laptop performing better than a model 520 conjures up an image in my mind of somebody running an Apache instance, a Websphere instance, a DB2 instance on their laptop. Web users are going along, getting okay performance. Then the laptop user launches something like Microsoft Outlook to check his mail, while performance tanks temporarily for Web users.
That may be a funny and extreme example, but it underscores the point that performance has more to do with the operating system, how workloads are managed, and software architecture, than the performance of dual-core vs. single-core CPUs.
Benchmark studies show that single core Power chips out-perform single-core Intel chips by a large margin. You make a valid point about dual-core Intel out-performing single-core Power, but I would strongly suggest that depends on the workload, and how you mange bottlenecks.
Have you ever noticed in benchmark studies that the number of application server instances they run, correlate closely with the number of cores on the server? In most cases, there's a one to one correlation. Otherwise the additional cores would be way underutilized. That illustrates how so much performance depends on workload management, which in the case of most operating systems, and under distributed architecture, must be configured manually. Otherwise performance sucks.
Contrast that with running applications under the native IBM environment, where the operating system synchronizes workloads automatically in most cases, for better overall performance.
Notwithstanding the foregoing, it appears to me that IBM is listening to concerns like yours, and addressing them with 8-core configurations on the Power 7 chip.
-Nathan.
midrange.com
