Messages in this thread |  | | Date | Sun, 18 Aug 2002 01:35:15 -0700 (PDT) | Subject | Re: Does Solaris really scale this well? | From | "David S. Miller" <> |
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From: Larry McVoy <lm@bitmover.com> Date: Sat, 17 Aug 2002 17:55:17 -0700
On Sun, Aug 18, 2002 at 12:03:24AM +0100, Ruth Ivimey-Cook wrote: > >> "When you take a 99-way UltraSPARC III machine and add a 100th processor, > >> you get 94 percent linear scalability. You can't get 94 percent linear > >> scalability on your first Intel chip. It's very, very hard to do, and they > >> have not done it." > > I've seen scientific reports of scalability that good in non-shared memory > computers (mostly in transputer arrays) where (with a scalable algorithm) > unless you got >90% you were doing something wrong. However, if you insist on > sharing main memory, I still don't believe you can get anywhere near that... > IMO 30% is doing very well once past the first few CPUs. Please reconsider your opinion. Both Sun and SGI scale past 100 CPUs on reasonable workloads in shared memory. Where "reasonable" != easy to do.
Also consider that if you start having performed so badly in the uniprocessor case like Solaris does, it doesn't take so much effort to get good scalability percentages as you add cpus because there isn't much to scale. :-)
To Sun's credit, they have on their side the fact that in the x86 world there still has never has been a very good large scale SMP backplane as of yet. At least not on the order of what you'd find on one of Sun's big boxes.
But in the same breath this is what will kill Sun in the end. Over time, the commodity stuff inches closer and closer to what Sun's "high end" is. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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