re: SMP scalability #
Posted Thursday 10th April 2008 01:03 GMT
Wow, this is obvious Sun competitor FUD, if I ever saw it. Either you're being spoon fed by (IBM?), or you work for them.
"1.7X the performance which means that adding the second chip only gives 70% more performance."
So what? IBM more than doubled their MHz from P5 to P6 and got less than a 1.6x performance increase based on SPECint2006. So what? They're still faster.
"Since you round robin the threads..."
This is nonsense... Well, not exactly nonsense, but lacks a great bit of understanding of how processors work (which of course, I myself am guilty of). The idea of Niagara is to take advantage of all the time that a thread is waiting on memory. Memory is inherently slow in relation to processors. Threads are constantly waiting on their next piece of information. In other architectures, this thread will then either have to go off CPU allowing another thread to get on the CPU, which is extremely expensive (taking several cycles). With Niagara, and T2, the CPU will just switch to another thread, which is all ready to run (taking 0 cycles).
To point at this as a weakness is just acknowledging that other platforms have a huge issue.
"Obviously, no one would ever use this system for Oracle since it requires 12 licenses..."
Another piece of nonsense. For one, Oracle is not the only game. Also, many companies have site licenses (which Oracle seems to prefer), so this is not an issue.
"Command line thread partitioning is unacceptable..."
Again, who cares??? You can control your use of threads via several means, including via a hypervisor (LDOMS), psrset, or even Containers. Seeing as Sun's competitors don't have domains on this class/price of system, and that IBM's "containers" are so new and not even supported by Oracle yet, I don't see the issue here. Of course, as you said, you manage the threads via command line, which is not that great... oh yeah, unless of course you own any other platform and have no threads to manage in the first place!
"Obviously the relationship with Fujitsu continues to be strained as the M-Class systems are deemphasized."
Huh? What the... Where'd this come from? Fujitsu is selling these systems under their own label. How does that... what?


