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Old 2010-01-15, 18:19   #6
R.D. Silverman
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Nov 2003

746010 Posts

Originally Posted by nucleon View Post
I have a corei7 920 (not over clocked, memory @1066MHz) that runs a NAS VM (amoungst other things), and runs mprime in the host OS.

Doing smb/cifs file transfers from the NAS VM to the host OS yields 15MB/sec (pretty consistant) when mprime is full throttle. (running 3x LL-Ds and 1x P-1)

With mprime turned off the same transfer increases to 20-25Mb/sec. In my testing process, I've made sure not to time cached transfers. (As a side issue - I've seen Linux cache cifs/smb transfers which is pretty cool. I haven't seen WinXP do the same.)

In my past experience, mprime (or is that an OS task?) is really good at throttling cpu cycles, but not memory bandwidth.

To me, this is a great example of memory saturation. So I'm leaning towards memory saturation at 6 cores with default clock speeds (memory @ 1066MHz-ish). But, hey if testing proves otherwise, then fair enough, I'll accept defeat :)

The new 8x real cores coming will defiantely hit memory saturation with memory @ 1066MHz-ish.

6 real cores at 1333HHz - subject to testing, I'm leaning away from memory saturation. It may just be aok.
8 real cores at 1333HHz - subject to testing, but I'm leaning towards memory saturation.

-- Craig
We need cache!! cache, cashe, and more cache!!! I want 8 Gbyte of
L2 cache!!!!
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