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January 13, 2008


Chen Shapira

I just discovered your blog and I can already see I'll spend the rest of the evening reading it.

Thats good information you have here.

According to Oracle, dNFS will scale better than kernel NFS if we use multiple NICs. Are you planning to test this?


Response by TOSG:

Already did. The testing we did used multiple NICs and we tested both kernel NFS with Linux bonding as well as dNFS. As I state in my post, the performance differences between kNFS and dNFS are washed out by the inferior memory model of 11g versus 10g. This is a case of a negative upgrade, i.e. a new feature which works worse the old one did. This makes 11g significantly less scalable than 10g, and thus dNFS buys you nothing. At some point I may spin up another 11g testbed and report this as a bug to Oracle. Right now, I am more focused on 10g and integrating that with our technology.

Kevin Closson

"Wrong. The memory model on the 64 bit version of 11g is no better than the 32 bit version. I find this very strange, and honestly consider it to be a bug."

Would you please do us a favor and tell us what you mean by "memory model?"

Krishna Manoharan

Hi Jeff,

Can you please post any stats you have collected (if possible)?

Krishna Manoharan

Dan Dressel

Hi Jeff,

Some very interesting information on your blog.

I'm in the process of testing 11g on the Linux x86-64 platform. What do you mean by an inferior memory model in 11g? Can you provide some specifics?

Are you referring to ASMM using the memory_max_target and the memory_target parameters? What problems are you seeing? Please share.




Could you please explain how 11g memory model is different from 10g and why, due to the difference, performance is worse ? Are database memory cache algorithms inferior, or is it something entirely different ?


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disclaimer: The opinions expressed here are my personal opinions. I am a blogger who works at EMC, not an EMC blogger. This is my blog, and not EMC's. Content published here is not read or approved in advance by EMC and does not necessarily reflect the views and opinions of EMC.